- Email: [email protected]
Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries
Journal of Colloid and Interface Science xxx (xxxx) xxx
Contents lists available at ScienceDirect
Journal of Colloid and Interface Science journal homepage: www.elsevier.com/locate/jcis
Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries Muhammad Asif b,⇑,1, Muhammad Rashad a,⇑,1, Jafar Hussain Shah c, Syed Danish Ali Zaidi d a
School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China c Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China d Advanced Rechargeable Batteries Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China b
h i g h l i g h t s
g r a p h i c a l a b s t r a c t
The SnO2-rGO composites were
A novel reduced graphene oxide (rGO) encapsulated tin oxide (SnO2) composite synthesized through an electrostatic-interaction-induced-self-assembly approach exhibited outstanding electrochemical properties for magnesium-ion batteries.
synthesized at low temperatures. Synthesized SnO2-rGO composites were tested as cathodes for Mg batteries. Mg batteries exhibited excellent specific capacities and capacity retentions. No volume expansion of SnO2 was observed in APC electrolyte.
a r t i c l e
i n f o
Article history: Received 23 October 2019 Revised 15 November 2019 Accepted 15 November 2019 Available online xxxx Keywords: Tin oxide Reduced graphene oxide Electrostatic – interaction – induced – self – assembly Electrochemical properties Mg-Ion batteries Energy storage
a b s t r a c t Among post-lithium ion technologies, magnesium-ion batteries (MIBs) are receiving great concern in recent years. However, MIBs are mainly restrained by the lack of cathode materials, which may accommodate the fast diffusion kinetics of Mg2+ ions. To overcome this problem, herein we attempt to synthesize a reduced graphene oxide (rGO) encapsulated tin oxide (SnO2) nanoparticles composites through an electrostatic-inter action-induced-self-assembly approach at low temperature. The surface modification of SnO2 via carbonaceous coating enhanced the electrical conductivity of final composites. The SnO2-rGO composites with different weight ratios of rGO and SnO2 are employed as cathode material in magnesium-ion batteries. Experimental results show that MIB exhibits a maximum specific capacity of 222 mAhg1 at the current density of 20 mAg1 with a good cycle life (capacity retention of 90%). Unlike Li-ion batteries, no SnO2 nanoparticles expansion is observed during electrochemical cycling in all-phenyl-complex (APC) magnesium electrolytes, which ultimately improves the capacity retention. Furthermore, ex-situ x-ray diffraction and scanning electron microscopy (SEM) studies are used to understand the magnesiation/de-magnesiation mechanisms. At the end, SnO2-rGO composites are tested for Mg2+/Li+ hybrid ion batteries and results reveal a specific capacity of 350 mAhg1 at the current density of 20 mAg1. However, hybrid ion battery exhibited sharp decay in capacity owing to volume expansion of SnO2 based cathodes. This work will provide a new insight for synthesis of electrode materials for energy storage devices. Ó 2019 Elsevier Inc. All rights reserved.
⇑ Corresponding authors. 1
E-mail addresses: [email protected] (M. Asif), [email protected] (M. Rashad). Equal contribution/co-first author.
https://doi.org/10.1016/j.jcis.2019.11.064 0021-9797/Ó 2019 Elsevier Inc. All rights reserved.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
2
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
1. Introduction The cleaner energy storage devices such as supercapacitors and batteries are becoming essential to support a pollution free society. The introduction of first lithium ion battery (LIB) in 1991 and constant research in this area resulted in large-scale commercialization of LIBs [1,2]. Although, LIBs have been extensively used in automotive, portable devices and grid stations, however it’s difficult to meet the ever increasing energy demands of portable devices as lithium ion technology has already approached to its theoretical limits [3]. Thus, it is essential to search for an alternative system with high natural abundance and energy density. In recent years magnesium ion batteries (MIBs) have emerged as an ideal post Li-ion system with several advantages over LIBs [4]. These advantages include existence of huge natural reserves of magnesium, high volumetric energy density (3833 mAh/cm3), low density, and divalent nature of Mg ions. More remarkably, the cycling process of MIBs is free of dendrite formation, thus reveal the Coulombic efficiency of 100% in compatible electrolytes [5,6]. In the past decades extensive efforts have been conducted to explore the reaction kinetics, high performance electrodes and compatible electrolytes for MIBs [7]. The performance of MIBs is still limited by poor control of reaction kinetics at the Mg metal and electrolyte interfaces [8]. Unlike lithium ion systems, the conventional electrolytes i.e. Mg(BF4)2/Mg(ClO4)2 dissolved in Acetonitrile/ Propylene carbonate, are not reversible as they form passive layer on magnesium anode [9,10]. For the first time, Gregory et al. [9] reported that Grignard reagent mixed in strong Lewis acid in ether solutions shows the complete reversibility of magnesium ions. However, the oxidation stability of these electrolytes was limited to 1.8 V, which is far from practical need of MIBs. Later, the groundbreaking work of Aurbach et al. [11] developed the organo-haloaluminate complexes dissolved in tetrahydrofuran (THF) as an effective electrolyte with an oxidation stability of 2.4 V verses Mg. These electrolytes demonstrated the acceptable intercalation kinetics and cycling stability, when employing the Chevrel phase Mo6S8 as cathode material. However, the specific capacity of this first prototype rechargeable MIBs was limited to 128 mAh/g. Since pioneering work of Aurbach et al. [11], extensive research has been conducted on synthesis of anode and cathode materials for MIBs. Manganese oxide is promising candidate owing to its low cost, high specific capacity, as well as high volumetric energy density, thus have been widely employed as positive electrodes in MIBs. Several attempts have recently been made to insert Mg2+ into alpha-MnO2 [12], Mn3O4 [13], and in Mg doped manganese oxides [14–16]. Furthermore, V2O5 [17–19], TiS2 [20,21], TiSe2 [22], Pressian blue [23,24], and TiO2 [25] were also employed as electrode materials in MIBs. However, these advances are still on an exploratory stage because of poor electrical conductivity of metal oxides and sluggish Mg2+ ion diffusions, which ultimately leads to high polarizations. Several strategies were used to overcome this issue, however was only limited to exploration of highly porous/nano-sized cathode materials or compatible electrolytes. Thus, an appropriate approach is needed to be explored, where fast Mg2+ kinetics is possible. Tin oxide, SnO2 is one of most widely used anode materials owing to its high natural abundance and high theoretical capacity i.e. 782 mAh/g. However, the main drawback, which hinders the practical application of SnO2 is its poor electrical conductivity. In present study, the electrical conductivity of SnO2 nanoparticles is enhanced by integrating them into graphene nanosheets by using an electrostatic self-assembly approach. The synthesized SnO2reduced graphene oxide composite (TO-rGO) were used as positive electrode in Mg ion batteries. To the best of our knowledge, this is first attempt, where surface modification of SnO2 via carbonaceous
coating is carried out, to optimize the interfacial properties of SnO2 and reaction kinetics of Mg2+ ion. More significantly, the proposed electrostatic-interaction-induced-self-assembly technique can also be used for the synthesis of other rGO-based composites at low temperatures. The TO-rGO composite based MIB exhibited high reversible capacities and excellent cycle life. Furthermore, cointercalation of Mg2+ and Li+ strategy is also employed to improve the reversibility of MIB. Co-intercalation of Mg2+ and Li+ could integrate the benefits of dendrite free Mg anode and fast kinetics of Li+ at cathode side, which ultimately boost up the electrochemical properties of MIBs [26]. 2. Experimental sections Graphene nanosheets decorated with SnO2 nanostructures were synthesized at a low temperature via electrostatic-interaction-ind uced self-assembly route. Graphene oxide (GO) was prepared according to the modified Hummer’s method [27]. Firstly, 50 ml of deionized water was added to 10 ml graphene oxide dispersion (3.85 wt% density) and sonicated for 2 h to make a uniform dispersion. Simultaneously, the SnO2 nanoparticles (0.25 g) were sonicated in 40 ml deionized water to make a uniform dispersion. Next, both dispersions were mixed and ultra-sonicated for another 1.0 h. Subsequently, 0.93 g of C6H8O6 (ascorbic acid) was added to the dispersion under stirring. The dispersion was maintained at 70 °C for 4.0 h in a water bath. Finally, the obtained black hydrogel was washed with deionized water and dried at 70 °C for 12 h, to obtain the SnO2-rGO (TO-rGO1) composite (Fig. 1). The TO-rGO2 composite was synthesized using similar procedure except the amount of SnO2 nanoparticles (1.0 g). The TO-rGO composites were characterized by X-ray diffraction (PANAlytical) equipped with Cu Ka radiation (40 kV, 40 mA, at k = 1.54 A) in 2h range of 15–85° at a scan rate of 0.02° s1. The thermal stabilities and carbon content of composites were examined using a thermogravimetic machine within temperature range of 30–700 °C. The Brunauer-Emmett-Teller (BET) technique was used to estimate the specific surface area of materials. The field emission scanning electron microscopy (FESEM, JEOL, JSM-7800F) equipped with electron dispersive X-ray spectroscopy and transmission electron microscopy (TEM, JEOL, JEM-2100) were used to examine the morphology of the composite powders and cycled electrodes. The electrodes were made of TO, TO-rGO1, or TO-rGO2, supper P, and polyvinylidene fluoride (PVDF) in a weight ratio of 70:20:10 using N-Methylpyrrolidone (NMP) as solvent. The electrode slurry was blended for 4 h and then coated onto a graphite foil. The coated foils were dried at 60 °C for 12 h and finally punched into a diameter of 14 mm. The All phenyl complex (0.4 APC) electrolyte was prepared as reported in our previous work [28] and for hybrid ion batteries, 1M lithium chloride were dissolved in APC electrolyte using stirring in glove box. The coin cells containing Mg metal anode, TO, TO-rGO1, or TO-rGO2 cathode, glass microfiber filter (GF/C) separator, and 0.4APC (for MIBs) or 0.4APC-1LiCl (for MLIB) electrolyte, were assembled in argon filled glove box. Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were carried out on an electrochemical workstation at the scan rate of 1.0 mV/s and 0.2–1.0 mV/s, respectively. The freshly prepared coin cells were tested for electrochemical performance using LANHE battery testing stations at room temperature in potential range of 0.05–2.0 V. 3. Results and discussion A low temperature electrostatic-interaction-induced selfassembly route is used to encapsulate the SnO2 nanoparticles
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
3
Fig. 1. Schematic diagram representing the electrostatic self-assembly approach for synthesis of TO-rGO composites and sketch of guest ions storage mechanism during redox reactions.
inside the rGO nanosheets as shown in Fig. 1. The GO dispersion in water possessing carboxyl and hydroxyl functional groups act as the anchoring site for any kind of positively charged nanoparticles colloidal (i.e. SnO2). Generally, the zeta (f) potentials of GO colloidal varies between 30 to 50 mV [29] and that of SnO2 colloidal varies between +20 to +45 mV [30]. Since SnO2 and GO dispersions are oppositely charged, thus when both dispersions are mixed the electrostatic attraction arises between them. As a result, driving force between oppositely charged components and strong van der Waals interactions lead to self-assembling process, which may lead to formation of GO nanosheets encapsulated SnO2 composite. This process can be seen in sketch diagram (Fig. 1), where a colloidal suspension was observed. In next step, addition of ascorbic acid into colloidal suspension at 70 °C and maintaining for about 4 h reduces the GO to graphene. At the same time, graphene decorated with SnO2 nanoparticles shrinks and changes into 3D shape as shown in sketch diagram. The presented technique is simple and can be used on large-scale production of metal oxidegraphene composites. The synthesized composites not only facilitate the fast electron transfer but may also control the huge volume expansion of SnO2 nanoparticles during redox reactions. X-ray diffraction study was carried out to examine the crystalline phases of TO, TO-rGO1, and TO-rGO2 composites after processing at 70 °C for 4 h as shown in Fig. 2(a). It can be seen that XRD peaks of TO can be indexed to tetragonal anatase (JCPDF#41-1445, Space group: P42/mnm(1 3 6)). Strong XRD peaks appearing at two theta equal to 26.61, 33.89, 37.94, 51.78, 54.75, 57.81, 61.87, 64.71, 65.93, 71.27, and 78.71° corresponds to (1 1 0), (1 0 1), (2 0 0), (2 1 1), (2 2 0), (0 0 2), (3 1 0), (1 1 2), (3 0 1), (2 0 2), and (3 2 1), respectively. The XRD peaks of TOrGO1 and TO-rGO2 composites are equivalent to that of pure TO with slight decrease in intensities. Interestingly, the diffraction
peak of graphene was not observed, which may be attributed to its low contents. The results indicate that the majority of TO nanoparticles retain their structural integrity even after processing at 70 °C for 4 h without formation of any impurity or second phase. Fig. 2(c) shows the thermogravimetic analysis curves of TO and its composites. It can be seen that TO do not exhibited weight loss, which revealed the high thermal stability of the material. On the other hand, composite samples showed weight loss of about 2– 3% between 30 and 150 °C, which is attributed to the removal of water vapors physical adsorbed on the surface of composite powders. When temperature was further increased from 150 to 400 °C, the weight loss values were increased to 9.28 and 6.99% for TOrGO1 and TO-rGO2 composite, respectively. These values can be expected as weight content of graphene sheets in the composites [31]. The presence of graphene sheets not only increase the electron transportations, but also confine the volume expansion of tin oxides, thus leading to high specific capacities. Fig. 2(d) represents the nitrogen absorption and desorption isotherms of TO and its composites. BET specific surface area of TO, TO-rGO1 and TOrGO2 composite were found to be 25.01, 98.6, and 70.5 m2g1, respectively. The increased specific surface area of composites is attributed to the presence of graphene sheets, which possesses higher specific surface area. The high surface area of material is beneficial for fast intercalation and de-intercalation of guest ions during redox reactions. Fig. 3(a)–(d) shows the SEM images of TO and its TO-rGO composites. It can be seen that TO particles reveal the size ranging from 200 to 400 nm and are agglomerated in the form of clusters as shown in Fig. 3(a). When these TO particles were sonicated and dispersed inside rGO solutions, they were attached to the surface of rGO nanosheets as shown in Fig. 3(b)–(d). After attachment, the surface of TO-rGO composite become rough and confirms the
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
4
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 2. (a) XRD profiles, (b) sketch model of SnO2 lattice created via VESTA software, (c) TGA, and (d) N2 absorption and desorption curves of pure TO nanostructures and its composites (TO-rGO1 and TO-rGO2).
uniform distribution of TO nanoparticles inside rGO nanosheets. The hydrophobic and p-p stacking interactions of the rGO nanosheets results in the formation of 3D interconnected networks, which have great capability to accommodate the guest ions during redox reactions. Fig. 3(e) confirmed that tin oxide particles (with very clear lattice fringes) are embedded inside the rGO matrix. To further confirm the distribution of TO nanoparticles inside the rGO network, energy dispersive X-ray spectroscopy was carried out for TO-rGO2 composite as shown in Fig. 3(f-i). It confirmed that TO nanoparticles were uniformly embedded inside rGO nanosheets network. The uniform distribution of TO nanoparticles is helpful for fast electron transportation. Linear sweep voltammetry (LSV) is used to explore the stability of current collector graphite and APC electrolytes at a potential scan rate of 1.0 mV/s. Fig. S1(a) reveals that an anodic current emerges at 2.8 V and keep increasing in the positive scan direction, which is attributed to decomposition of the electrolyte [11]. Furthermore, CV curve of GFkAPCkMg cell at the potential scan rate of 5.0 mV/s is shown in Fig. S1(b). The CV curve from 0.5 to 2.8 V confirms the magnesium deposition/dissolution (as proved by XRD curves shown in Fig. S2) and decomposition of APC electrolyte. After the characterization of electrolyte/current collector stability, CV is carried out for TO-rGO2kAPCkMg cell at different scan rates (0.2–1.0 mV/s) to evaluate the diffusion of Mg2+ ion as shown in Fig. 4(a) and (b). The Fig. 4(a) shows the 1st, 2nd, 3rd, 4th, 5th, and 6th CV cycles of TO-rGO2kAPCkMg cell at the scan rate of 0.5 mV/s. It can be seen that 1st CV cycle is different from subsequent cycles, which is attributed to the formation of solid electrolyte interface (SEI) on the surface of cathode [32]. The subsequent cycles exhibit distinct oxidation peaks at about 1.26, 1.05, and 0.76 V and corresponding reduction peaks are present at 0.79, and 0.36 V. The presence of several oxidation or reduction peaks reveals the multistep insertion process and corresponds to small plateaus as shown in charging/discharging curves in Fig. 5(b)–(d). Furthermore, it was observed that intensity of peaks increases with
number of cycles, which is due to activation process and thus specific capacity increases in first few cycles as shown in Fig. 5 (e). For example, TO-rGO2kAPCkMg cell exhibits the specific capacity of 115 mAh/g during 2nd cycle and increased to a maximum value of 165 mAh/g after few cycles due to activation process. Fig. 4(b) shows that increasing scan rate will increase the peak currents both in anodic and cathodic sides. These highly symmetrical peaks signify the good reversibility [33]. The relation between peak current (I) and scan rate (V) is shown by the following equation:
I ¼ aV b
ð1Þ
where a and b are constants. The b = 1 indicates the pseudocapacitive behavior and b = 0.5 indicates the diffusion behavior of the guest ions [34,35]. Fig. S3 shows the relationship between log(peak current) and log(scan rate), where calculated b values for peaks 1, 2, and 3 were found to be 0.61, 0.79, and 0.78, respectively. It indicates that redox reactions are dominated by both diffusion and surface controlled reactions mainly due to the unique sandwich structure of TO-rGO2 composite. To confirm the contribution of diffusion and surface controlled process following equation was employed.
iðVÞ ¼ k1 v þ k2 v 1=2
ð2Þ
where k1 v and k2 v 1=2 represents the surface and diffusion controlled contribution behaviors. The constants k1 and k2 were calculated and both pseudocapacitive contribution and diffusion contribution for magnesium storage were quantified as a function of scan rates as shown in Fig. 4(c) and (d) [35,36]. It can be seen that at low scan rate, the cathode is dominated by diffusion process (i.e. diffusion contribution was 66.6% at 0.2 mV/s with distinct cathodic peaks). However, at high scan rate (i.e. 1.0 mV/s), the diffusion contribution reduces to the value of 25.5% as confirmed by suppressed cathode peaks in Fig. 4(b). It was confirmed that increasing scan rate would increase the pseudocapacitive behavior and is highly favorable for rGO-based composites.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
5
Fig. 3. SEM images showing morphologies of (a) TO nanostructures, (b–c) low and high magnification images of TO-rGO1, (d) TO-rGO2 composites, (e) TEM of TO-rGO1 composite, and (f–i) Energy dispersive X-ray spectroscopy showing the distribution of TO particles inside the rGO nanosheets: (f) TO-rGO2 composite, (g) Carbon (rGO), (h) Element Oxygen, and (i) Element Tin.
The galvanostatic discharge-charge measurements were carried out to investigate the electrochemical properties of TO, TO-rGO1 and TO-rGO2 composites at room temperatures with a potential
range of 0.05–2.0 V. The Fig. 5(a) represents the rate performance of synthesized electrode materials at the current densities ranging from 0.02 to 1.0 A/g. It can be seen that TO cathode reveals specific
Fig. 4. Cyclic voltammetry of TO-rGO2kAPCkMg cell: (a) 1st to 6th CV profiles at the scan rate of 0.5 mV/s, (b) CV profiles at 0.2, 0.5, and 1.0 mV/s scan rates, (c) Histogram showing the variations of pseudocapacitive contribution and diffusion contribution for magnesium storage along with scan rates, and (d) CV curve with the pseudocapacitive fraction shown by the shaded region at a scan rate of 0.5 mV/s.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
6
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 5. Electrochemical performances of TO, TO-rGO1 and TO-rGO2 composite electrodes for Mg2+ ion batteries: (a) Rate performance at different current densities, (b) Galvanostatic charge/discharge profiles of TO cathode under various current densities, (c) Galvanostatic charge/discharge profiles of TO-rGO2 composite under various current densities, (d) 2nd, 25th, and 100th charge-discharge profiles of TO-rGO2 composite at 100 mA/g, and (e) Long-term cyclic performance at 0.10 A/g.
capacity of about 127 mAh/g, which keeps decreasing in first few cycles. On the other hand, TO-rGO1 and TO-rGO2 composites reveal higher and stable specific capacities at all current densities. The increased capacity of TO-rGO1 and TO-rGO2 materials is attributed to their higher electronic conductivity due to presence of grapheme [37]. The TO-rGO2 composite electrode reveals highest values of specific capacities i.e. 222 mAh/g. After cycling the electrodes at different current densities (0.02–1.0 A/g) and returning to initial current density value (0.02 A/g), the specific capacities of cathodes were recovered with 99.5% coulombic efficiency. The Fig. 5(b) and (c) represents the galvanostatic charge/discharge profiles of TO and TO-rGO2 composite at various current densities. Careful observation reveals that there are several small plateaus, which correspond to multistep insertion and extraction of Mg2+ ions as confirmed by the CV measurements. The capacity retentions of TO, TO-rGO1 and TO-rGO2 composite electrodes are examined by cycling the MIBs at 0.10 A/g as shown in Fig. 5(e). It can be observed that discharge capacities of both composites (TO-rGO1 and TO-rGO2) increases in first few cycles due to activation process as confirmed by CV results. Both composites revealed excellent capacity retentions i.e. 90.05% and 89.1% for TO-rGO1 and TOrGO2, respectively for 150 cycles. The corresponding 2nd, 25th,
and 100th galvanostatic charge/discharge profiles of TO-rGO2 composite at 0.10 A/g are shown in Fig. 5(d). The capacity retentions of synthesized electrodes are higher than previously reported MIB based electrodes. For example, RFC/V2O5 [19], poly(ethylene oxide) intercalated V2O5 [38], alpha-MnO2 [12], Mg0.15MnO20.9H2O [21], and TiS2 [39] revealed the capacity retention of 62.5%, 69.23%, 33.3%, 31.2%, and 78.57% respectively. Furthermore, the specific capacities of previously reported cathodes for MIBs are compared with present work at different current densities as shown in Fig. 6(a). The high rate performance and capacity retention of our composites are attributed to the presence of graphene nanosheets, which retains the structural integrity of tin oxide nanoparticles along with high electrical conductivity. To further elaborated the advantages of present work in terms of synthesis procedures, improvement in capacities and capacity retentions, several literature reports such as FeVO40.9H2O/Graphene [17], V2O5 nH2O@rGO [40], Mn3O4/GO [41], Mn3O4/rGO [41], Bi/rGO [42], and MgMn2O4/rGO [43] synthesized using different techniques are summarized and compared (with present work) in Table 1. It can be noticed that present work outperformed previous reports owing to its simple synthesis and excellent capacity retentions. Literature review revealed that C.H. Zhang et al. [44]
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
have synthesized the tin nanoparticles based reduced graphene oxide nanocomposites (Sn/rGO) using hydrothermal method for magnesium ion batteries. The synthesized Sn/rGO composite electrodes were tested in all-phenyl-complex (PhMgCl-AlCl3-THF) electrolyte solutions between 0.0 and 1.3 V. The resultant battery exhibited impressive specific capacity (around 545 mAh/g at the current density of 15 mA/g) with stable charge-discharge voltage plateaus. Although, the capacity was significantly higher, however the battery exhibited fast decay in capacity (during first 20 cycles). More importantly, the working potential of battery was very low (around 0.24 V). The estimated values of specific energies were found to be 120, 96, 84, 60, and 52 Wh/kg at the power densities of 3.6, 7.2, 14.4, 36, and 72 W/kg, respectively as shown in Fig. S4. On the other hand, present work revealed much better performance when using TO-rGO composites. Firstly, the TO-rGO composites exhibited much better working voltage i.e. between 0.95 and 1.0 V. Secondly, the specific energies delivered by TO-rGO composites are much higher than that of Sn/rGO composite. For example, the TO-rGO2 composite electrode revealed the specific energies of 211, 181,143, 114, 82, and 45 Wh/kg at the power densities of 19, 38, 95, 190, 380, and 950 W/kg, respectively (Fig. S4) [44]. Thus, comparison clearly revealed the advantages of tin oxide over metallic tin nanoparticle based composite electrodes for magnesium ion batteries. Generally, cut-off potential window is an important factor affecting the long-term stability of electrode materials through conversion reactions and crystal structure evolution during the redox reactions. Literature review revealed that there are limited reports in this area [3,28]. Furthermore, cut-off potential window is also directly related to electrolytes stabilities. Therefore, it is very important to investigate the influence of cut-off voltage on cycle stabilities of MIBs. To specifically examine, firstly both TO and TO-rGO1 electrodes were cycled in APC electrolytes at cutoff voltages of 2.0, 2.2, 2.4, 2.6, and 2.8 V for 20 cycles as shown in Fig. S5 (a). It can be noticed that both charge and discharge capacities increase with increase in cut-off potential window. The coulombic efficiencies are close to 99.99% even for the cut-off potential window of 2.4 V. When MIBs are cycled at cut-off potential window equals to 2.6 V, the coulombic efficiencies are decreased to values of about 97.53%. During this potential widow, a steady rise in specific capacities of TO-rGO1 electrode is observed, which is due to activation process. When cut-off potential window of 2.8 V is used, an abrupt fall in both capacity and coulombic efficiency is observed. The decrease in electrochemical properties of MIB at higher cut-off potential is associated with the decomposition of APC electrolytes [28]. The result in Fig. S5 (a) reveals that MIBs can be cycled at a maximum cut-off voltage of 2.6 V, thus composite electrodes were cycled at 2.4 and 2.6 V. When MIB is directly cycled with 2.4 or 2.6 V cut-off potential, charging curve could not fully charge. Therefore, MIBs are cycled with stepwise increase in cut-off potentials as shown in Fig. S5 (b) and (c). It can be seen that TO-rGO2 electrode exhibit the capacity retentions of 35.63% and 41.17% for 2.4 and 2.6 V cut-off voltages respectively. On the other hand, TO-rGO1 electrode founds to be more stable at cut-off voltage of 2.4 V with capacity retention of 73.1%. These results indicated that capacity decay at higher cutoff voltage is dependent on structural integrity of electrode materials, electrolyte stabilities and assembly of cells [45]. To further investigate this effect, in-situ studies are required, which will be carried out in our future work. To further boost up the specific capacity of MIBs, we introduced the co-intercalation of Mg2+ and Li+ strategy by adding small amount of lithium chloride. The co-intercalation of Mg2+/Li+ ions allows not only highly reversible magnesium plating and stripping but also permits fast insertion and extraction of lithium ions on the positive electrode. Furthermore, it bypasses the problem of
7
magnesium diffusion inside the positive electrodes and potentially unsafe dendrites formations. In our previous study, we have investigated the effect of molar concentrations of LiCl added into APC electrolytes, which revealed that 0.4MAPC-1.0MLiCl exhibits highest specific capacities [46,47]. Thus, the 0.4MAPC-1.0MLiCl in THF is used as electrolytes for Mg2+/Li+ hybrid ion cells. Fig. S6(a) presents the cyclic voltammograms performed in hybrid electrolytes at 0.5 mV/s in a potential window of 0.0–2.0 V. It can be seen that relatively low current and broad peaks are observed during first cycle. This is attributed to lithium storage reaction i.e. formation of solid electrolyte interface (SEI). Furthermore, the conversion of Li to LiO2 and SnO2 to metallic Sn is carried out. In subsequent cycles several oxidation peaks (at 0.32, 0.95 V) and reduction (at 0.44, 0.85 V) peaks confirm the high reversibility and multistep alloying/de-alloying reaction of LixSn, which have been well elaborated in previous studies [37]. Furthermore, a pair of oxidation (0.25 V) and reduction (0.15 V) peaks is attributed to lithiation/ delithiation of reduced graphene oxide as confirmed by previous studies [48]. The possible reaction at SnO2 based cathode can be written as. þ
SnO2 þ 4Li þ 4e ! 2Li2 O þ Sn þ
Sn þ xLi þ xe $ Lix Snð0 6 x 6 4:4Þ
ð3Þ ð4Þ
Literature review reveals that tin oxide has been extensively used in lithium ion batteries. Interestingly, unlike SnO2 based LIBs electrodes which exhibit sharp capacity decay due to large volume expansion of tin oxide, is not seen in our MIBs. Thus, SnO2 based electrodes were further used for Mg2+/Li+ hybrid ion batteries as shown in Fig. S6(b)–(d). To examine the ultrafast charging/discharging capabilities of TO and TO-rGO1 electrodes, hybrid cells were cycled at current densities ranging from 20 to 1000 mA/g. Fig. S6(b) shows the rate capability where discharge capacities of 260 and 350 mAh/g were exhibited by pure TO and TO-rGO1, respectively at 20 mA/g. Increase in applied current density reduced the discharge capacities of both materials. The discharge capacity of 268 mAh/g can be measured when the current density reduces back to 20 mA/g, which indicates a high stability as well as excellent reversibility of TO-rGO1. The Galvanostatic charge/discharge profiles of TO-rGO1 composite at various current densities are shown in Fig. S6(c). Noticeably, the improved rate capability and specific capacity of TO-rGO1 composite compared with pristine TO is because the coating of SnO2 nanoparticles by rGO sheets protects the nanoparticles from severe structural degradation during lithiation/delithiation. Furthermore, rGO nanosheets improve the electrical conductivity of SnO2 nanoparticles, which ultimately boost up electron transportation during redox reactions. The cycle stability profiles of pure TO and TO-rGO1 at 100 mA/g current density are shown in Fig. S6(d). It can be seen that TO-rGO1 based MLIB cell reveal the specific capacity of 160 and 131 mAh/g after 50 and 100 cycles. The electrochemical impedance spectroscopic (EIS) study is carried out on fully activated MIB half-cells as shown in Fig. 6(b). The equivalent circuit shown in Fig. S7 describes the electrochemical reaction steps. It contains bulk resistance Rb (electrolyte, electrodes, and separator), electron transfer resistance Re or capacitance CPEe at SEI and Mg2+ ion diffusion resistance Ri or capacitance CPEi, in high and low frequency regions. W1 is Warburg impedance representing Mg2+ diffusion inside the cathode. The Z-view software was used to evaluate the EIS data. Careful observation revealed that TO-rGO1 and TO-rGO2 composites with high electrical conductivities exhibited the lower resistance values (900 and 809 Ohm) compared with bare TO cathode as shown in Fig. 6(b). The inset of Fig. 6(b) shows the plot between Z’ and x-1/2 in low frequency region, where x is angular frequency
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
8
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 6. (a) Comparison of the specific capacities between TO-rGO2 (present work) and other reported Mg-storage cathode materials [28,51–54], (b) Nyquist plots with inset showing plot between Z’ and x-1/2 in low frequency region (Frequency range: 106–0.01 Hz), Ex-situ XRD profiles of (c) TO, and (d) TO-rGO2 cycled in APC electrolytes at different charge stages.
Table 1 Comparison of present work with previously reported rGO based composites in magnesium ion batteries. Composites
System
Capacity Improvement (%)
Capacity Retention (%) [Cycles]
References
FeVO40.9H2O/Graphene V2O5 nH2O@rGO Mn3O4/GO Mn3O4/rGO Bi/rGO MgMn2O4/rGO TO-rGO2
Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion
18.91 64.15 54.67 58.13 21.68 38.01 45.45
90 81 95 96 88 74 98
[17] [40] [41] [41] [42] [43] Present Work
(x = 2pf). The low gradient slopes of both composites indicated the higher Mg2+ ion diffusivity in the TO-rGO1 and TO-rGO2 structures compared to that of bare TO structure. Thus, faster electrochemical kinetics promoted the specific capacities of both composites [49]. Ex-situ XRD is used to investigate the effect of charge states on TO or TO-rGO2 composite structures during insertion/extraction of Mg2+ ions. For this purpose, the electrodes (TO or TO-rGO2) were cycled at 100 mA/g in APC/APC-LiCl electrolytes and then charged/discharged to the desired potentials. Ex-situ XRD profile of TO or TO-rGO2 powders reveals strong peaks at two theta equal to 26.50, 33.63, 37.85, and 51.52°. On the other hand, assembled electrode reveals only two distinct peaks at two theta equal to 33.63 and 51.52° corresponding to active material as shown in Fig. 6 (c-d). It can be seen that pristine electrode or charged TO electrodes reveal the distinct peaks at two theta equal to 33.63 and 51.52° as shown in Fig. 6(c). When the TO electrode is discharged in APC electrolytes to 1.0 or 0.0 V, the peaks at 33.63° and 51.52° shift towards higher angles, which is attributed to insertion of Mg2+ ions inside the TO lattices. These changes correlate the fast kinetics and variations in the lattice parameters of tin oxide during insertion/extraction of Mg2+ ions [46]. In case of TOrGO2 electrode (Fig. 6(d)), the distinct peaks at two theta equal
[50] [200] [20] [700] [50] [1000] [150]
to 33.63 and 51.52° corresponding to active material also shift towards higher angles. However, the changes in peak positions were not significant in case of TO-rGO2 cathode. This might be attributed to the presence of graphene sheets around the tin oxide nanoparticles, which facilitates the surface charge storage instead of diffusion inside the tin oxide lattices [28,37]. However, detailed process is still unknown due to lack of interfacial studies in this area. Additionally, ex-situ XRD study for TO-rGO1 electrode cycled in APC-LiCl electrolyte is also carried out as shown in Fig. S8. However, peaks related to active material were not observed after cycling. This is because SnO2 is covered by an unstable solid electrolyte interphase (SEI), which blocks the passage of ions during cycling process thus leading to rapid capacity decay as discussed in electrochemical characterization part. The same phenomenon was also observed during the lithiation of tin oxides nanowires in previous works [50]. SEM equipped with EDS is used to examine the microstructural changes before and after cycling in Mg2+ and Mg2+/Li+ hybrid electrolytes as shown in Fig. 7. It can be seen that TO-rGO1 electrode displays the SnO2 nanoparticles with 50 nm size embedded uniformly in graphene nanosheets (Fig. 7(a)). The corresponding EDS profile confirms the presence of SnO2 nanoparticles, carbon black,
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
9
Fig. 7. (a) Freshly prepared TO-rGO1 electrode, (b) EDS of selected area in (a); (c) TO-rGO1 electrode cycled in APC electrolytes, (d) EDS of selected area in (c); (e) TO-rGO1 electrode cycled in APC-LiCl electrolytes and (f) EDS of selected area in (e) (insets show high magnification images).
and binder as shown by peaks (Fig. 7(b)). The electrodes were cycled in APC and APC-LiCl electrolytes for about 100 cycles and examined in charged states. The SEM of electrode cycled in APC electrolyte reveals increase in particle size of SnO2 nanoparticles, which is about 85 nm as shown in Fig. 7(c). However, the volume expansion is not as high as observed in LIBs (~250%). Thus, SnO2 is promising anode materials for MIBs with stable SEI and shows long cycle life as discussed in electrochemical characterization parts. The EDS of selected part shows the presence of additional peaks corresponding to Mg as shown in Fig. 7(d), which might be due to trapping of some Mg2+ and is consistent with previous work [28,47,55]. Fig. 7(e) shows the morphology of electrode cycled in APC-LiCl electrolyte, where swear volume expansion of SnO2 and unstable SEI (due to presence of LiCl) can be clearly seen in magnified image. This is because crystalline SnO2 nanoparticles decrystallize and agglomerate into large volume globules, which ultimately fracture during cycling [28,37,56]. Therefore, loss of
electrical integrity of electrodes leads to rapid capacity fading during charging/discharging process. 4. Conclusions To summarize, we have presented a new strategy to synthesize SnO2-rGO composites at low temperature via electrostatic-interac tion-induced self-assembly approach. The synthesized composites are tested as electrode materials for Mg and Mg/Li hybrid ion batteries. Interestingly, no volume expansion of SnO2 nanoparticles was observed during magnesiation and de-magnesiation. The MIB cells exhibited the maximum specific capacity of 222 mAh/g at a current density of 20 mA/g and excellent capacity retentions (90.05%). Furthermore, co-intercalation of Mg2+ and Li+ ions revealed a maximum specific capacity of 350 mAh/g at a current density of 20 mA/g. However, capacity retentions of MLIBs are not as good as for MIB, which is attributed to volume expansion
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
10
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
of SnO2 nanoparticles due to presence of LiCl. Additionally, effect of cut-off voltages, ex-situ XRD, and EIS studies were carried out to understand the basic electrochemical mechanism. This study establishes that tin oxide encapsulated in rGO is a promising candidate for high-performance and potentially safe MIB cathodes. Author contributions Muhammad Asif and Muhammad Rashad performed the experiments, analyzed the data, wrote the initial manuscript draft and finalized the manuscript for submission on equal contribution basis. Jafar Hussain Shah and Syed Danish Ali Zaidi participated in discussions of the results. All authors have reviewed the manuscript. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgement This research was supported by National Natural Science Foundation of China (51601073), Jiangsu Distinguished Professor Project (1064901601), Jiangsu Provincial Six Talent Peaks Project (1062991801), and Jiangsu University of Science and Technology Research Start-Up Fund (1062921905). Appendix A. Supplementary material Supplementary data to this article can be found online at https://doi.org/10.1016/j.jcis.2019.11.064. References [1] V. Etacheri, R. Marom, R. Elazari, G. Salitra, D. Aurbach, Challenges in the development of advanced Li-ion batteries: a review, Energy Environ. Sci. 4 (9) (2011) 3243–3262, https://doi.org/10.1039/C1EE01598B. [2] A. Manthiram, Materials challenges and opportunities of lithium ion batteries, J. Phys. Chem. Lett. 2 (3) (2011) 176–184, https://doi.org/10.1021/jz1015422. [3] Z. Sun, J. Zhang, L. Yin, G. Hu, R. Fang, H.-M. Cheng, F. Li, Conductive porous vanadium nitride/graphene composite as chemical anchor of polysulfides for lithium-sulfur batteries, Nat. Commun. 8 (2017) 14627, https://doi.org/ 10.1038/ncomms14627. [4] J. Muldoon, C.B. Bucur, T. Gregory, Quest for nonaqueous multivalent secondary batteries: magnesium and beyond, Chem. Rev. 114 (23) (2014) 11683–11720, https://doi.org/10.1021/cr500049y. [5] M. Rashad, F. Pan, Z. Yu, M. Asif, H. Lin, R. Pan, Investigation on microstructural, mechanical and electrochemical properties of aluminum composites reinforced with graphene nanoplatelets, Prog. Natl. Sci.: Mater. Int. 25 (5) (2015) 460–470, https://doi.org/10.1016/j.pnsc.2015.09.005. [6] P. Saha, M.K. Datta, O.I. Velikokhatnyi, A. Manivannan, D. Alman, P.N. Kumta, Rechargeable magnesium battery: current status and key challenges for the future, Prog. Mater Sci. 66 (2014) 1–86, https://doi.org/10.1016/j.pmatsci. 2014.04.001. [7] M.M. Huie, D.C. Bock, E.S. Takeuchi, A.C. Marschilok, K.J. Takeuchi, Cathode materials for magnesium and magnesium-ion based batteries, Coord. Chem. Rev. 287 (2015) 15–27, https://doi.org/10.1016/j.ccr.2014.11.005. [8] O. Tutusaus, R. Mohtadi, N. Singh, T.S. Arthur, F. Mizuno, Study of electrochemical phenomena observed at the Mg metal/electrolyte interface, ACS Energy Lett. 2 (1) (2017) 224–229, https://doi.org/10.1021/acsenergy lett.6b00549. [9] T.D. Gregory, R.J. Hoffman, R.C. Winterton, Nonaqueous electrochemistry of magnesium: applications to energy storage, J. Electrochem. Soc. 137 (3) (1990) 775–780, https://doi.org/10.1149/1.2086553. [10] D. Aurbach, Y. Gofer, A. Schechter, O. Chusid, H. Gizbar, Y. Cohen, M. Moshkovich, R. Turgeman, A comparison between the electrochemical behavior of reversible magnesium and lithium electrodes, J. Power Sources 97–98 (2001) 269–273, https://doi.org/10.1016/S0378-7753(01)00622-X. [11] D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, E. Levi, Prototype systems for rechargeable magnesium batteries, Nature 407 (2000) 724, https://doi.org/10.1038/35037553.
[12] R. Zhang, X. Yu, K.-W. Nam, C. Ling, T.S. Arthur, W. Song, A.M. Knapp, S.N. Ehrlich, X.-Q. Yang, M. Matsui, a-MnO2 as a cathode material for rechargeable Mg batteries, Electrochem. Commun. 23 (2012) 110–113, https://doi.org/ 10.1016/j.elecom.2012.07.021. [13] L. Wang, K. Asheim, P.E. Vullum, A.M. Svensson, F. Vullum-Bruer, Sponge-like porous manganese(II, III) oxide as a highly efficient cathode material for rechargeable magnesium ion batteries, Chem. Mater. 28 (18) (2016) 6459– 6470, https://doi.org/10.1021/acs.chemmater.6b01016. [14] H. Zhang, K. Ye, X. Huang, X. Wang, K. Cheng, X. Xiao, G. Wang, D. Cao, Preparation of Mg1.1Mn6O124.5H2O with nanobelt structure and its application in aqueous magnesium-ion battery, J. Power Sources 338 (2017) 136–144, https://doi.org/10.1016/j.jpowsour.2016.10.078. [15] J. Yin, A.B. Brady, E.S. Takeuchi, A.C. Marschilok, K.J. Takeuchi, Magnesium-ion battery-relevant electrochemistry of MgMn2O4: crystallite size effects and the notable role of electrolyte water content, Chem. Commun. 53 (26) (2017) 3665–3668, https://doi.org/10.1039/C7CC00265C. [16] Q.D. Truong, M. Kempaiah Devaraju, P.D. Tran, Y. Gambe, K. Nayuki, Y. Sasaki, I. Honma, Unravelling the surface structure of MgMn2O4 cathode materials for rechargeable magnesium-ion battery, Chem. Mater. 29 (15) (2017) 6245– 6251, https://doi.org/10.1021/acs.chemmater.7b01252. [17] H. Zhang, K. Ye, K. Zhu, R. Cang, J. Yan, K. Cheng, G. Wang, D. Cao, The FeVO40.9H2O/Graphene composite as anode in aqueous magnesium ion battery, Electrochim. Acta 256 (2017) 357–364, https://doi.org/10.1016/ j.electacta.2017.10.038. [18] S. Tepavcevic, Y. Liu, D. Zhou, B. Lai, J. Maser, X. Zuo, H. Chan, P. Král, C.S. Johnson, V. Stamenkovic, N.M. Markovic, T. Rajh, Nanostructured layered cathode for rechargeable Mg-ion batteries, ACS Nano 9 (8) (2015) 8194–8205, https://doi.org/10.1021/acsnano.5b02450. [19] Y. Cheng, Y. Shao, V. Raju, X. Ji, B.L. Mehdi, K.S. Han, M.H. Engelhard, G. Li, N.D. Browning, K.T. Mueller, J. Liu, Molecular storage of Mg ions with vanadium oxide nanoclusters, Adv. Funct. Mater. 26 (20) (2016) 3446–3453, https://doi. org/10.1002/adfm.201505501. [20] Z.-L. Tao, L.-N. Xu, X.-L. Gou, J. Chen, H.-T. Yuan, TiS2 nanotubes as the cathode materials of Mg-ion batteries, Chem. Commun. 18 (2004) 2080–2081, https:// doi.org/10.1039/B403855J. [21] X. Sun, V. Duffort, B.L. Mehdi, N.D. Browning, L.F. Nazar, Investigation of the mechanism of Mg insertion in birnessite in nonaqueous and aqueous rechargeable Mg-ion batteries, Chem. Mater. 28 (2) (2016) 534–542, https:// doi.org/10.1021/acs.chemmater.5b03983. [22] Y. Gu, Y. Katsura, T. Yoshino, H. Takagi, K. Taniguchi, Rechargeable magnesium-ion battery based on a TiSe2-cathode with d-p orbital hybridized electronic structure, Sci. Rep. 5 (2015) 12486, https://doi.org/ 10.1038/srep12486 https://www.nature.com/articles/srep12486#supplementaryinformation. [23] X. Sun, V. Duffort, L.F. Nazar, Prussian blue MgLi hybrid batteries, Adv. Sci. 3 (8) (2016), https://doi.org/10.1002/advs.201600044. 1600044-n/a. [24] R.Y. Wang, C.D. Wessells, R.A. Huggins, Y. Cui, Highly reversible open framework nanoscale electrodes for divalent ion batteries, Nano Lett. 13 (11) (2013) 5748–5752, https://doi.org/10.1021/nl403669a. [25] T. Koketsu, J. Ma, B.J. Morgan, M. Body, C. Legein, W. Dachraoui, M. Giannini, A. Demortière, M. Salanne, F. Dardoize, H. Groult, O.J. Borkiewicz, K.W. Chapman, P. Strasser, D. Dambournet, Reversible magnesium and aluminium ions insertion in cation-deficient anatase TiO2, Nat. Mater. 16 (2017) 1142, https://doi.org/10.1038/nmat4976. [26] X. Bian, Y. Gao, Q. Fu, S. Indris, Y. Ju, Y. Meng, F. Du, N. Bramnik, H. Ehrenberg, Y. Wei, A long cycle-life and high safety Na+/Mg2+ hybrid-ion battery built by using a TiS2 derived titanium sulfide cathode, J. Mater. Chem. A 5 (2) (2017) 600–608, https://doi.org/10.1039/C6TA08505A. [27] A.M. Dimiev, J.M. Tour, Mechanism of graphene oxide formation, ACS Nano 8 (3) (2014) 3060–3068, https://doi.org/10.1021/nn500606a. [28] M. Rashad, H. Zhang, M. Asif, K. Feng, X. Li, H. Zhang, Low-cost roomtemperature synthesis of NaV3O81.69H2O nanobelts for Mg batteries, ACS Appl. Mater. Interfaces 10 (5) (2018) 4757–4766, https://doi.org/10.1021/ acsami.7b18682. [29] K. Krishnamoorthy, M. Veerapandian, K. Yun, S.J. Kim, The chemical and structural analysis of graphene oxide with different degrees of oxidation, Carbon 53 (2013) 38–49, https://doi.org/10.1016/j.carbon. 2012.10.013. [30] S.A.A. Aziz, S.H. Amirnordin, H.A. Rahman, H.Z. Abdullah, H. Taib, Effect of zeta potential of stanum oxide (SnO2) on electrophoretic deposition (EPD) on porous alumina, Adv. Mater. Res. 795 (2013) 334–337. [31] M. Rashad, h. zhang, X. Li, H. Zhang, Fast kinetics of Mg2+/Li+ hybrid ions in polyanion Li3V2(PO4)3 cathode in wide temperature range, J. Mater. Chem. A (2019), https://doi.org/10.1039/C9TA00502A. [32] Y. Cheng, L.R. Parent, Y. Shao, C. Wang, V.L. Sprenkle, G. Li, J. Liu, Facile synthesis of chevrel phase nanocubes and their applications for multivalent energy storage, Chem. Mater. 26 (17) (2014) 4904–4907, https://doi.org/ 10.1021/cm502306c. [33] Z. Zhang, H. Xu, Z. Cui, P. Hu, J. Chai, H. Du, J. He, J. Zhang, X. Zhou, P. Han, G. Cui, L. Chen, High energy density hybrid Mg2+/Li+ battery with superior ultralow temperature performance, J. Mater. Chem. A 4 (6) (2016) 2277–2285, https://doi.org/10.1039/C5TA09591C. [34] H.-S. Kim, J.B. Cook, H. Lin, Jesse S. Ko, Sarah H. Tolbert, V. Ozolins, B. Dunn, Oxygen vacancies enhance pseudocapacitive charge storage properties of MoO3x, Nat. Mater. 16 (2016) 454, https://doi.org/ 10.1038/nmat4810.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx [35] J. Wang, J. Polleux, J. Lim, B. Dunn, Pseudocapacitive contributions to electrochemical energy storage in TiO2 (Anatase) nanoparticles, J. Phys. Chem. C 111 (40) (2007) 14925–14931, https://doi.org/10.1021/ jp074464w. [36] X. Xie, M.-Q. Zhao, B. Anasori, K. Maleski, C.E. Ren, J. Li, B.W. Byles, E. Pomerantseva, G. Wang, Y. Gogotsi, Porous heterostructured MXene/carbon nanotube composite paper with high volumetric capacity for sodium-based energy storage devices, Nano Energy 26 (2016) 513–523, https://doi.org/ 10.1016/j.nanoen.2016.06.005. [37] Y. Dong, Z. Zhao, Z. Wang, Y. Liu, X. Wang, J. Qiu, Dually fixed SnO2 nanoparticles on graphene nanosheets by polyaniline coating for superior lithium storage, ACS Appl. Mater. Interfaces 7 (4) (2015) 2444–2451, https:// doi.org/10.1021/am506818h. [38] S.D. Perera, R.B. Archer, C.A. Damin, R. Mendoza-Cruz, C.P. Rhodes, Controlling interlayer interactions in vanadium pentoxide-poly(ethylene oxide) nanocomposites for enhanced magnesium-ion charge transport and storage, J. Power Sources 343 (2017) 580–591, https://doi.org/10.1016/j.jpowsour. 2017.01.052. [39] X. Sun, P. Bonnick, L.F. Nazar, Layered TiS2 positive electrode for Mg batteries, ACS Energy Lett. 1 (1) (2016) 297–301, https://doi.org/10.1021/ acsenergylett.6b00145. [40] Q. An, Y. Li, H. Deog Yoo, S. Chen, Q. Ru, L. Mai, Y. Yao, Graphene decorated vanadium oxide nanowire aerogel for long-cycle-life magnesium battery cathodes, Nano Energy 18 (2015) 265–272, https://doi.org/10.1016/ j.nanoen.2015.10.029. [41] L. Wang, P.E. Vullum, K. Asheim, X. Wang, A.M. Svensson, F. Vullum-Bruer, High capacity Mg batteries based on surface-controlled electrochemical reactions, Nano Energy 48 (2018) 227–237, https://doi.org/10.1016/ j.nanoen.2018.03.061. [42] T.R. Penki, G. Valurouthu, S. Shivakumara, V.A. Sethuraman, N. Munichandraiah, In situ synthesis of bismuth (Bi)/reduced graphene oxide (RGO) nanocomposites as high-capacity anode materials for a Mg-ion battery, New J. Chem. 42 (8) (2018) 5996–6004, https://doi.org/10.1039/C7NJ04930G. [43] G. Liu, Q. Chi, Y. Zhang, Q. Chen, C. Zhang, K. Zhu, D. Cao, Superior high rate capability of MgMn2O4/rGO nanocomposites as cathode materials for aqueous rechargeable magnesium ion batteries, Chem. Commun. 54 (68) (2018) 9474– 9477, https://doi.org/10.1039/C8CC05366A. [44] L.N. Zhang Changhuan, Yao Hurong, Liu Lin, Yin Yaxia, Guo Yuguo, Synthesis of Sn nanoparticles/graphenenanosheet hybrid electrode material with threedimensional conducting network for magnesium storage, Acta Chim. Sinica 75 (2017) 206–211, https://doi.org/10.6023/A16100542. [45] X. Ou, X. Liang, F. Zheng, P. Wu, Q. Pan, X. Xiong, C. Yang, M. Liu, In situ X-ray diffraction investigation of CoSe2 anode for Na-ion storage: Effect of cut-off
[46]
[47]
[48]
[49]
[50]
[51]
[52]
[53]
[54]
[55]
[56]
11
voltage on cycling stability, Electrochim. Acta 258 (2017) 1387–1396, https:// doi.org/10.1016/j.electacta.2017.11.198. M. Rashad, X. Li, H. Zhang, Magnesium/lithium-ion hybrid battery with high reversibility by employing NaV3O81.69H2O nanobelts as a positive electrode, ACS Appl. Mater. Interfaces 10 (25) (2018) 21313–21320, https://doi.org/ 10.1021/acsami.8b04139. M. Asif, M. Rashad, Z. Ali, H. Qiu, W. Li, L. Pan, Y. Hou, Ni-doped MnO2/CNT nanoarchitectures as a cathode material for ultra-long life magnesium/lithium hybrid ion batteries, Mater. Today Energy 10 (2018) 108–117, https://doi.org/ 10.1016/j.mtener.2018.08.010. E. Frackowiak, F. Béguin, Electrochemical storage of energy in carbon nanotubes and nanostructured carbons, Carbon 40 (10) (2002) 1775–1787, https://doi.org/10.1016/S0008-6223(02)00045-3. J.H. Choi, S.-K. Park, Y.C. Kang, A salt-templated strategy toward hollow iron selenides-graphitic carbon composite microspheres with interconnected multicavities as high-performance anode materials for sodium-ion batteries, Small 15 (2) (2019) 1803043, https://doi.org/10.1002/smll.201803043. J.Y. Huang, L. Zhong, C.M. Wang, J.P. Sullivan, W. Xu, L.Q. Zhang, S.X. Mao, N.S. Hudak, X.H. Liu, A. Subramanian, H. Fan, In situ observation of the electrochemical lithiation of a single SnO2 nanowire electrode, Science 330 (6010) (2010) 1515–1520, https://doi.org/10.1126/science.1195628. X. Deng, Y. Xu, Q. An, F. Xiong, S. Tan, L. Wu, L. Mai, Manganese ion preintercalated hydrated vanadium oxide as a high-performance cathode for magnesium ion batteries, J. Mater. Chem. A 7 (17) (2019) 10644–10650, https://doi.org/10.1039/C8TA11236C. F. Liu, Y. Liu, X. Zhao, X. Liu, L.-Z. Fan, Pursuit of a high-capacity and long-life Mg-storage cathode by tailoring sandwich-structured MXene@carbon nanosphere composites, J. Mater. Chem. A (2019), https://doi.org/10.1039/ C9TA02212K. K. Liang, K. Marcus, L. Guo, Z. Li, L. Zhou, Y. Li, S.T. De Oliveira, N. Orlovskaya, Y. H. Sohn, Y. Yang, A freestanding NiSx porous film as a binder-free electrode for Mg-ion batteries, Chem. Commun. 53 (54) (2017) 7608–7611, https://doi.org/ 10.1039/C7CC03517A. Y. Meng, D. Wang, Y. Zhao, R. Lian, Y. Wei, X. Bian, Y. Gao, F. Du, B. Liu, G. Chen, Ultrathin TiO2-B nanowires as an anode material for Mg-ion batteries based on a surface Mg storage mechanism, Nanoscale 9 (35) (2017) 12934–12940, https://doi.org/10.1039/C7NR03493H. M. Rashad, M. Asif, Y. Wang, Z. He, I. Ahmed, Recent advances in electrolytes and cathode materials for magnesium and hybrid-ion batteries, Energy Storage Mater. (2019), https://doi.org/10.1016/j.ensm.2019.10.004. M. Rashad, H. Zhang, X. Li, H. Zhang, Fast kinetics of Mg2+/Li+ hybrid ions in a polyanion Li3V2(PO4)3 cathode in a wide temperature range, J. Mater. Chem. A 7 (16) (2019) 9968–9976, https://doi.org/10.1039/C9TA00502A.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
Contents lists available at ScienceDirect
Journal of Colloid and Interface Science journal homepage: www.elsevier.com/locate/jcis
Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries Muhammad Asif b,⇑,1, Muhammad Rashad a,⇑,1, Jafar Hussain Shah c, Syed Danish Ali Zaidi d a
School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China c Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China d Advanced Rechargeable Batteries Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China b
h i g h l i g h t s
g r a p h i c a l a b s t r a c t
The SnO2-rGO composites were
A novel reduced graphene oxide (rGO) encapsulated tin oxide (SnO2) composite synthesized through an electrostatic-interaction-induced-self-assembly approach exhibited outstanding electrochemical properties for magnesium-ion batteries.
synthesized at low temperatures. Synthesized SnO2-rGO composites were tested as cathodes for Mg batteries. Mg batteries exhibited excellent specific capacities and capacity retentions. No volume expansion of SnO2 was observed in APC electrolyte.
a r t i c l e
i n f o
Article history: Received 23 October 2019 Revised 15 November 2019 Accepted 15 November 2019 Available online xxxx Keywords: Tin oxide Reduced graphene oxide Electrostatic – interaction – induced – self – assembly Electrochemical properties Mg-Ion batteries Energy storage
a b s t r a c t Among post-lithium ion technologies, magnesium-ion batteries (MIBs) are receiving great concern in recent years. However, MIBs are mainly restrained by the lack of cathode materials, which may accommodate the fast diffusion kinetics of Mg2+ ions. To overcome this problem, herein we attempt to synthesize a reduced graphene oxide (rGO) encapsulated tin oxide (SnO2) nanoparticles composites through an electrostatic-inter action-induced-self-assembly approach at low temperature. The surface modification of SnO2 via carbonaceous coating enhanced the electrical conductivity of final composites. The SnO2-rGO composites with different weight ratios of rGO and SnO2 are employed as cathode material in magnesium-ion batteries. Experimental results show that MIB exhibits a maximum specific capacity of 222 mAhg1 at the current density of 20 mAg1 with a good cycle life (capacity retention of 90%). Unlike Li-ion batteries, no SnO2 nanoparticles expansion is observed during electrochemical cycling in all-phenyl-complex (APC) magnesium electrolytes, which ultimately improves the capacity retention. Furthermore, ex-situ x-ray diffraction and scanning electron microscopy (SEM) studies are used to understand the magnesiation/de-magnesiation mechanisms. At the end, SnO2-rGO composites are tested for Mg2+/Li+ hybrid ion batteries and results reveal a specific capacity of 350 mAhg1 at the current density of 20 mAg1. However, hybrid ion battery exhibited sharp decay in capacity owing to volume expansion of SnO2 based cathodes. This work will provide a new insight for synthesis of electrode materials for energy storage devices. Ó 2019 Elsevier Inc. All rights reserved.
⇑ Corresponding authors. 1
E-mail addresses: [email protected] (M. Asif), [email protected] (M. Rashad). Equal contribution/co-first author.
https://doi.org/10.1016/j.jcis.2019.11.064 0021-9797/Ó 2019 Elsevier Inc. All rights reserved.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
2
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
1. Introduction The cleaner energy storage devices such as supercapacitors and batteries are becoming essential to support a pollution free society. The introduction of first lithium ion battery (LIB) in 1991 and constant research in this area resulted in large-scale commercialization of LIBs [1,2]. Although, LIBs have been extensively used in automotive, portable devices and grid stations, however it’s difficult to meet the ever increasing energy demands of portable devices as lithium ion technology has already approached to its theoretical limits [3]. Thus, it is essential to search for an alternative system with high natural abundance and energy density. In recent years magnesium ion batteries (MIBs) have emerged as an ideal post Li-ion system with several advantages over LIBs [4]. These advantages include existence of huge natural reserves of magnesium, high volumetric energy density (3833 mAh/cm3), low density, and divalent nature of Mg ions. More remarkably, the cycling process of MIBs is free of dendrite formation, thus reveal the Coulombic efficiency of 100% in compatible electrolytes [5,6]. In the past decades extensive efforts have been conducted to explore the reaction kinetics, high performance electrodes and compatible electrolytes for MIBs [7]. The performance of MIBs is still limited by poor control of reaction kinetics at the Mg metal and electrolyte interfaces [8]. Unlike lithium ion systems, the conventional electrolytes i.e. Mg(BF4)2/Mg(ClO4)2 dissolved in Acetonitrile/ Propylene carbonate, are not reversible as they form passive layer on magnesium anode [9,10]. For the first time, Gregory et al. [9] reported that Grignard reagent mixed in strong Lewis acid in ether solutions shows the complete reversibility of magnesium ions. However, the oxidation stability of these electrolytes was limited to 1.8 V, which is far from practical need of MIBs. Later, the groundbreaking work of Aurbach et al. [11] developed the organo-haloaluminate complexes dissolved in tetrahydrofuran (THF) as an effective electrolyte with an oxidation stability of 2.4 V verses Mg. These electrolytes demonstrated the acceptable intercalation kinetics and cycling stability, when employing the Chevrel phase Mo6S8 as cathode material. However, the specific capacity of this first prototype rechargeable MIBs was limited to 128 mAh/g. Since pioneering work of Aurbach et al. [11], extensive research has been conducted on synthesis of anode and cathode materials for MIBs. Manganese oxide is promising candidate owing to its low cost, high specific capacity, as well as high volumetric energy density, thus have been widely employed as positive electrodes in MIBs. Several attempts have recently been made to insert Mg2+ into alpha-MnO2 [12], Mn3O4 [13], and in Mg doped manganese oxides [14–16]. Furthermore, V2O5 [17–19], TiS2 [20,21], TiSe2 [22], Pressian blue [23,24], and TiO2 [25] were also employed as electrode materials in MIBs. However, these advances are still on an exploratory stage because of poor electrical conductivity of metal oxides and sluggish Mg2+ ion diffusions, which ultimately leads to high polarizations. Several strategies were used to overcome this issue, however was only limited to exploration of highly porous/nano-sized cathode materials or compatible electrolytes. Thus, an appropriate approach is needed to be explored, where fast Mg2+ kinetics is possible. Tin oxide, SnO2 is one of most widely used anode materials owing to its high natural abundance and high theoretical capacity i.e. 782 mAh/g. However, the main drawback, which hinders the practical application of SnO2 is its poor electrical conductivity. In present study, the electrical conductivity of SnO2 nanoparticles is enhanced by integrating them into graphene nanosheets by using an electrostatic self-assembly approach. The synthesized SnO2reduced graphene oxide composite (TO-rGO) were used as positive electrode in Mg ion batteries. To the best of our knowledge, this is first attempt, where surface modification of SnO2 via carbonaceous
coating is carried out, to optimize the interfacial properties of SnO2 and reaction kinetics of Mg2+ ion. More significantly, the proposed electrostatic-interaction-induced-self-assembly technique can also be used for the synthesis of other rGO-based composites at low temperatures. The TO-rGO composite based MIB exhibited high reversible capacities and excellent cycle life. Furthermore, cointercalation of Mg2+ and Li+ strategy is also employed to improve the reversibility of MIB. Co-intercalation of Mg2+ and Li+ could integrate the benefits of dendrite free Mg anode and fast kinetics of Li+ at cathode side, which ultimately boost up the electrochemical properties of MIBs [26]. 2. Experimental sections Graphene nanosheets decorated with SnO2 nanostructures were synthesized at a low temperature via electrostatic-interaction-ind uced self-assembly route. Graphene oxide (GO) was prepared according to the modified Hummer’s method [27]. Firstly, 50 ml of deionized water was added to 10 ml graphene oxide dispersion (3.85 wt% density) and sonicated for 2 h to make a uniform dispersion. Simultaneously, the SnO2 nanoparticles (0.25 g) were sonicated in 40 ml deionized water to make a uniform dispersion. Next, both dispersions were mixed and ultra-sonicated for another 1.0 h. Subsequently, 0.93 g of C6H8O6 (ascorbic acid) was added to the dispersion under stirring. The dispersion was maintained at 70 °C for 4.0 h in a water bath. Finally, the obtained black hydrogel was washed with deionized water and dried at 70 °C for 12 h, to obtain the SnO2-rGO (TO-rGO1) composite (Fig. 1). The TO-rGO2 composite was synthesized using similar procedure except the amount of SnO2 nanoparticles (1.0 g). The TO-rGO composites were characterized by X-ray diffraction (PANAlytical) equipped with Cu Ka radiation (40 kV, 40 mA, at k = 1.54 A) in 2h range of 15–85° at a scan rate of 0.02° s1. The thermal stabilities and carbon content of composites were examined using a thermogravimetic machine within temperature range of 30–700 °C. The Brunauer-Emmett-Teller (BET) technique was used to estimate the specific surface area of materials. The field emission scanning electron microscopy (FESEM, JEOL, JSM-7800F) equipped with electron dispersive X-ray spectroscopy and transmission electron microscopy (TEM, JEOL, JEM-2100) were used to examine the morphology of the composite powders and cycled electrodes. The electrodes were made of TO, TO-rGO1, or TO-rGO2, supper P, and polyvinylidene fluoride (PVDF) in a weight ratio of 70:20:10 using N-Methylpyrrolidone (NMP) as solvent. The electrode slurry was blended for 4 h and then coated onto a graphite foil. The coated foils were dried at 60 °C for 12 h and finally punched into a diameter of 14 mm. The All phenyl complex (0.4 APC) electrolyte was prepared as reported in our previous work [28] and for hybrid ion batteries, 1M lithium chloride were dissolved in APC electrolyte using stirring in glove box. The coin cells containing Mg metal anode, TO, TO-rGO1, or TO-rGO2 cathode, glass microfiber filter (GF/C) separator, and 0.4APC (for MIBs) or 0.4APC-1LiCl (for MLIB) electrolyte, were assembled in argon filled glove box. Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were carried out on an electrochemical workstation at the scan rate of 1.0 mV/s and 0.2–1.0 mV/s, respectively. The freshly prepared coin cells were tested for electrochemical performance using LANHE battery testing stations at room temperature in potential range of 0.05–2.0 V. 3. Results and discussion A low temperature electrostatic-interaction-induced selfassembly route is used to encapsulate the SnO2 nanoparticles
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
3
Fig. 1. Schematic diagram representing the electrostatic self-assembly approach for synthesis of TO-rGO composites and sketch of guest ions storage mechanism during redox reactions.
inside the rGO nanosheets as shown in Fig. 1. The GO dispersion in water possessing carboxyl and hydroxyl functional groups act as the anchoring site for any kind of positively charged nanoparticles colloidal (i.e. SnO2). Generally, the zeta (f) potentials of GO colloidal varies between 30 to 50 mV [29] and that of SnO2 colloidal varies between +20 to +45 mV [30]. Since SnO2 and GO dispersions are oppositely charged, thus when both dispersions are mixed the electrostatic attraction arises between them. As a result, driving force between oppositely charged components and strong van der Waals interactions lead to self-assembling process, which may lead to formation of GO nanosheets encapsulated SnO2 composite. This process can be seen in sketch diagram (Fig. 1), where a colloidal suspension was observed. In next step, addition of ascorbic acid into colloidal suspension at 70 °C and maintaining for about 4 h reduces the GO to graphene. At the same time, graphene decorated with SnO2 nanoparticles shrinks and changes into 3D shape as shown in sketch diagram. The presented technique is simple and can be used on large-scale production of metal oxidegraphene composites. The synthesized composites not only facilitate the fast electron transfer but may also control the huge volume expansion of SnO2 nanoparticles during redox reactions. X-ray diffraction study was carried out to examine the crystalline phases of TO, TO-rGO1, and TO-rGO2 composites after processing at 70 °C for 4 h as shown in Fig. 2(a). It can be seen that XRD peaks of TO can be indexed to tetragonal anatase (JCPDF#41-1445, Space group: P42/mnm(1 3 6)). Strong XRD peaks appearing at two theta equal to 26.61, 33.89, 37.94, 51.78, 54.75, 57.81, 61.87, 64.71, 65.93, 71.27, and 78.71° corresponds to (1 1 0), (1 0 1), (2 0 0), (2 1 1), (2 2 0), (0 0 2), (3 1 0), (1 1 2), (3 0 1), (2 0 2), and (3 2 1), respectively. The XRD peaks of TOrGO1 and TO-rGO2 composites are equivalent to that of pure TO with slight decrease in intensities. Interestingly, the diffraction
peak of graphene was not observed, which may be attributed to its low contents. The results indicate that the majority of TO nanoparticles retain their structural integrity even after processing at 70 °C for 4 h without formation of any impurity or second phase. Fig. 2(c) shows the thermogravimetic analysis curves of TO and its composites. It can be seen that TO do not exhibited weight loss, which revealed the high thermal stability of the material. On the other hand, composite samples showed weight loss of about 2– 3% between 30 and 150 °C, which is attributed to the removal of water vapors physical adsorbed on the surface of composite powders. When temperature was further increased from 150 to 400 °C, the weight loss values were increased to 9.28 and 6.99% for TOrGO1 and TO-rGO2 composite, respectively. These values can be expected as weight content of graphene sheets in the composites [31]. The presence of graphene sheets not only increase the electron transportations, but also confine the volume expansion of tin oxides, thus leading to high specific capacities. Fig. 2(d) represents the nitrogen absorption and desorption isotherms of TO and its composites. BET specific surface area of TO, TO-rGO1 and TOrGO2 composite were found to be 25.01, 98.6, and 70.5 m2g1, respectively. The increased specific surface area of composites is attributed to the presence of graphene sheets, which possesses higher specific surface area. The high surface area of material is beneficial for fast intercalation and de-intercalation of guest ions during redox reactions. Fig. 3(a)–(d) shows the SEM images of TO and its TO-rGO composites. It can be seen that TO particles reveal the size ranging from 200 to 400 nm and are agglomerated in the form of clusters as shown in Fig. 3(a). When these TO particles were sonicated and dispersed inside rGO solutions, they were attached to the surface of rGO nanosheets as shown in Fig. 3(b)–(d). After attachment, the surface of TO-rGO composite become rough and confirms the
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
4
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 2. (a) XRD profiles, (b) sketch model of SnO2 lattice created via VESTA software, (c) TGA, and (d) N2 absorption and desorption curves of pure TO nanostructures and its composites (TO-rGO1 and TO-rGO2).
uniform distribution of TO nanoparticles inside rGO nanosheets. The hydrophobic and p-p stacking interactions of the rGO nanosheets results in the formation of 3D interconnected networks, which have great capability to accommodate the guest ions during redox reactions. Fig. 3(e) confirmed that tin oxide particles (with very clear lattice fringes) are embedded inside the rGO matrix. To further confirm the distribution of TO nanoparticles inside the rGO network, energy dispersive X-ray spectroscopy was carried out for TO-rGO2 composite as shown in Fig. 3(f-i). It confirmed that TO nanoparticles were uniformly embedded inside rGO nanosheets network. The uniform distribution of TO nanoparticles is helpful for fast electron transportation. Linear sweep voltammetry (LSV) is used to explore the stability of current collector graphite and APC electrolytes at a potential scan rate of 1.0 mV/s. Fig. S1(a) reveals that an anodic current emerges at 2.8 V and keep increasing in the positive scan direction, which is attributed to decomposition of the electrolyte [11]. Furthermore, CV curve of GFkAPCkMg cell at the potential scan rate of 5.0 mV/s is shown in Fig. S1(b). The CV curve from 0.5 to 2.8 V confirms the magnesium deposition/dissolution (as proved by XRD curves shown in Fig. S2) and decomposition of APC electrolyte. After the characterization of electrolyte/current collector stability, CV is carried out for TO-rGO2kAPCkMg cell at different scan rates (0.2–1.0 mV/s) to evaluate the diffusion of Mg2+ ion as shown in Fig. 4(a) and (b). The Fig. 4(a) shows the 1st, 2nd, 3rd, 4th, 5th, and 6th CV cycles of TO-rGO2kAPCkMg cell at the scan rate of 0.5 mV/s. It can be seen that 1st CV cycle is different from subsequent cycles, which is attributed to the formation of solid electrolyte interface (SEI) on the surface of cathode [32]. The subsequent cycles exhibit distinct oxidation peaks at about 1.26, 1.05, and 0.76 V and corresponding reduction peaks are present at 0.79, and 0.36 V. The presence of several oxidation or reduction peaks reveals the multistep insertion process and corresponds to small plateaus as shown in charging/discharging curves in Fig. 5(b)–(d). Furthermore, it was observed that intensity of peaks increases with
number of cycles, which is due to activation process and thus specific capacity increases in first few cycles as shown in Fig. 5 (e). For example, TO-rGO2kAPCkMg cell exhibits the specific capacity of 115 mAh/g during 2nd cycle and increased to a maximum value of 165 mAh/g after few cycles due to activation process. Fig. 4(b) shows that increasing scan rate will increase the peak currents both in anodic and cathodic sides. These highly symmetrical peaks signify the good reversibility [33]. The relation between peak current (I) and scan rate (V) is shown by the following equation:
I ¼ aV b
ð1Þ
where a and b are constants. The b = 1 indicates the pseudocapacitive behavior and b = 0.5 indicates the diffusion behavior of the guest ions [34,35]. Fig. S3 shows the relationship between log(peak current) and log(scan rate), where calculated b values for peaks 1, 2, and 3 were found to be 0.61, 0.79, and 0.78, respectively. It indicates that redox reactions are dominated by both diffusion and surface controlled reactions mainly due to the unique sandwich structure of TO-rGO2 composite. To confirm the contribution of diffusion and surface controlled process following equation was employed.
iðVÞ ¼ k1 v þ k2 v 1=2
ð2Þ
where k1 v and k2 v 1=2 represents the surface and diffusion controlled contribution behaviors. The constants k1 and k2 were calculated and both pseudocapacitive contribution and diffusion contribution for magnesium storage were quantified as a function of scan rates as shown in Fig. 4(c) and (d) [35,36]. It can be seen that at low scan rate, the cathode is dominated by diffusion process (i.e. diffusion contribution was 66.6% at 0.2 mV/s with distinct cathodic peaks). However, at high scan rate (i.e. 1.0 mV/s), the diffusion contribution reduces to the value of 25.5% as confirmed by suppressed cathode peaks in Fig. 4(b). It was confirmed that increasing scan rate would increase the pseudocapacitive behavior and is highly favorable for rGO-based composites.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
5
Fig. 3. SEM images showing morphologies of (a) TO nanostructures, (b–c) low and high magnification images of TO-rGO1, (d) TO-rGO2 composites, (e) TEM of TO-rGO1 composite, and (f–i) Energy dispersive X-ray spectroscopy showing the distribution of TO particles inside the rGO nanosheets: (f) TO-rGO2 composite, (g) Carbon (rGO), (h) Element Oxygen, and (i) Element Tin.
The galvanostatic discharge-charge measurements were carried out to investigate the electrochemical properties of TO, TO-rGO1 and TO-rGO2 composites at room temperatures with a potential
range of 0.05–2.0 V. The Fig. 5(a) represents the rate performance of synthesized electrode materials at the current densities ranging from 0.02 to 1.0 A/g. It can be seen that TO cathode reveals specific
Fig. 4. Cyclic voltammetry of TO-rGO2kAPCkMg cell: (a) 1st to 6th CV profiles at the scan rate of 0.5 mV/s, (b) CV profiles at 0.2, 0.5, and 1.0 mV/s scan rates, (c) Histogram showing the variations of pseudocapacitive contribution and diffusion contribution for magnesium storage along with scan rates, and (d) CV curve with the pseudocapacitive fraction shown by the shaded region at a scan rate of 0.5 mV/s.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
6
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 5. Electrochemical performances of TO, TO-rGO1 and TO-rGO2 composite electrodes for Mg2+ ion batteries: (a) Rate performance at different current densities, (b) Galvanostatic charge/discharge profiles of TO cathode under various current densities, (c) Galvanostatic charge/discharge profiles of TO-rGO2 composite under various current densities, (d) 2nd, 25th, and 100th charge-discharge profiles of TO-rGO2 composite at 100 mA/g, and (e) Long-term cyclic performance at 0.10 A/g.
capacity of about 127 mAh/g, which keeps decreasing in first few cycles. On the other hand, TO-rGO1 and TO-rGO2 composites reveal higher and stable specific capacities at all current densities. The increased capacity of TO-rGO1 and TO-rGO2 materials is attributed to their higher electronic conductivity due to presence of grapheme [37]. The TO-rGO2 composite electrode reveals highest values of specific capacities i.e. 222 mAh/g. After cycling the electrodes at different current densities (0.02–1.0 A/g) and returning to initial current density value (0.02 A/g), the specific capacities of cathodes were recovered with 99.5% coulombic efficiency. The Fig. 5(b) and (c) represents the galvanostatic charge/discharge profiles of TO and TO-rGO2 composite at various current densities. Careful observation reveals that there are several small plateaus, which correspond to multistep insertion and extraction of Mg2+ ions as confirmed by the CV measurements. The capacity retentions of TO, TO-rGO1 and TO-rGO2 composite electrodes are examined by cycling the MIBs at 0.10 A/g as shown in Fig. 5(e). It can be observed that discharge capacities of both composites (TO-rGO1 and TO-rGO2) increases in first few cycles due to activation process as confirmed by CV results. Both composites revealed excellent capacity retentions i.e. 90.05% and 89.1% for TO-rGO1 and TOrGO2, respectively for 150 cycles. The corresponding 2nd, 25th,
and 100th galvanostatic charge/discharge profiles of TO-rGO2 composite at 0.10 A/g are shown in Fig. 5(d). The capacity retentions of synthesized electrodes are higher than previously reported MIB based electrodes. For example, RFC/V2O5 [19], poly(ethylene oxide) intercalated V2O5 [38], alpha-MnO2 [12], Mg0.15MnO20.9H2O [21], and TiS2 [39] revealed the capacity retention of 62.5%, 69.23%, 33.3%, 31.2%, and 78.57% respectively. Furthermore, the specific capacities of previously reported cathodes for MIBs are compared with present work at different current densities as shown in Fig. 6(a). The high rate performance and capacity retention of our composites are attributed to the presence of graphene nanosheets, which retains the structural integrity of tin oxide nanoparticles along with high electrical conductivity. To further elaborated the advantages of present work in terms of synthesis procedures, improvement in capacities and capacity retentions, several literature reports such as FeVO40.9H2O/Graphene [17], V2O5 nH2O@rGO [40], Mn3O4/GO [41], Mn3O4/rGO [41], Bi/rGO [42], and MgMn2O4/rGO [43] synthesized using different techniques are summarized and compared (with present work) in Table 1. It can be noticed that present work outperformed previous reports owing to its simple synthesis and excellent capacity retentions. Literature review revealed that C.H. Zhang et al. [44]
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
have synthesized the tin nanoparticles based reduced graphene oxide nanocomposites (Sn/rGO) using hydrothermal method for magnesium ion batteries. The synthesized Sn/rGO composite electrodes were tested in all-phenyl-complex (PhMgCl-AlCl3-THF) electrolyte solutions between 0.0 and 1.3 V. The resultant battery exhibited impressive specific capacity (around 545 mAh/g at the current density of 15 mA/g) with stable charge-discharge voltage plateaus. Although, the capacity was significantly higher, however the battery exhibited fast decay in capacity (during first 20 cycles). More importantly, the working potential of battery was very low (around 0.24 V). The estimated values of specific energies were found to be 120, 96, 84, 60, and 52 Wh/kg at the power densities of 3.6, 7.2, 14.4, 36, and 72 W/kg, respectively as shown in Fig. S4. On the other hand, present work revealed much better performance when using TO-rGO composites. Firstly, the TO-rGO composites exhibited much better working voltage i.e. between 0.95 and 1.0 V. Secondly, the specific energies delivered by TO-rGO composites are much higher than that of Sn/rGO composite. For example, the TO-rGO2 composite electrode revealed the specific energies of 211, 181,143, 114, 82, and 45 Wh/kg at the power densities of 19, 38, 95, 190, 380, and 950 W/kg, respectively (Fig. S4) [44]. Thus, comparison clearly revealed the advantages of tin oxide over metallic tin nanoparticle based composite electrodes for magnesium ion batteries. Generally, cut-off potential window is an important factor affecting the long-term stability of electrode materials through conversion reactions and crystal structure evolution during the redox reactions. Literature review revealed that there are limited reports in this area [3,28]. Furthermore, cut-off potential window is also directly related to electrolytes stabilities. Therefore, it is very important to investigate the influence of cut-off voltage on cycle stabilities of MIBs. To specifically examine, firstly both TO and TO-rGO1 electrodes were cycled in APC electrolytes at cutoff voltages of 2.0, 2.2, 2.4, 2.6, and 2.8 V for 20 cycles as shown in Fig. S5 (a). It can be noticed that both charge and discharge capacities increase with increase in cut-off potential window. The coulombic efficiencies are close to 99.99% even for the cut-off potential window of 2.4 V. When MIBs are cycled at cut-off potential window equals to 2.6 V, the coulombic efficiencies are decreased to values of about 97.53%. During this potential widow, a steady rise in specific capacities of TO-rGO1 electrode is observed, which is due to activation process. When cut-off potential window of 2.8 V is used, an abrupt fall in both capacity and coulombic efficiency is observed. The decrease in electrochemical properties of MIB at higher cut-off potential is associated with the decomposition of APC electrolytes [28]. The result in Fig. S5 (a) reveals that MIBs can be cycled at a maximum cut-off voltage of 2.6 V, thus composite electrodes were cycled at 2.4 and 2.6 V. When MIB is directly cycled with 2.4 or 2.6 V cut-off potential, charging curve could not fully charge. Therefore, MIBs are cycled with stepwise increase in cut-off potentials as shown in Fig. S5 (b) and (c). It can be seen that TO-rGO2 electrode exhibit the capacity retentions of 35.63% and 41.17% for 2.4 and 2.6 V cut-off voltages respectively. On the other hand, TO-rGO1 electrode founds to be more stable at cut-off voltage of 2.4 V with capacity retention of 73.1%. These results indicated that capacity decay at higher cutoff voltage is dependent on structural integrity of electrode materials, electrolyte stabilities and assembly of cells [45]. To further investigate this effect, in-situ studies are required, which will be carried out in our future work. To further boost up the specific capacity of MIBs, we introduced the co-intercalation of Mg2+ and Li+ strategy by adding small amount of lithium chloride. The co-intercalation of Mg2+/Li+ ions allows not only highly reversible magnesium plating and stripping but also permits fast insertion and extraction of lithium ions on the positive electrode. Furthermore, it bypasses the problem of
7
magnesium diffusion inside the positive electrodes and potentially unsafe dendrites formations. In our previous study, we have investigated the effect of molar concentrations of LiCl added into APC electrolytes, which revealed that 0.4MAPC-1.0MLiCl exhibits highest specific capacities [46,47]. Thus, the 0.4MAPC-1.0MLiCl in THF is used as electrolytes for Mg2+/Li+ hybrid ion cells. Fig. S6(a) presents the cyclic voltammograms performed in hybrid electrolytes at 0.5 mV/s in a potential window of 0.0–2.0 V. It can be seen that relatively low current and broad peaks are observed during first cycle. This is attributed to lithium storage reaction i.e. formation of solid electrolyte interface (SEI). Furthermore, the conversion of Li to LiO2 and SnO2 to metallic Sn is carried out. In subsequent cycles several oxidation peaks (at 0.32, 0.95 V) and reduction (at 0.44, 0.85 V) peaks confirm the high reversibility and multistep alloying/de-alloying reaction of LixSn, which have been well elaborated in previous studies [37]. Furthermore, a pair of oxidation (0.25 V) and reduction (0.15 V) peaks is attributed to lithiation/ delithiation of reduced graphene oxide as confirmed by previous studies [48]. The possible reaction at SnO2 based cathode can be written as. þ
SnO2 þ 4Li þ 4e ! 2Li2 O þ Sn þ
Sn þ xLi þ xe $ Lix Snð0 6 x 6 4:4Þ
ð3Þ ð4Þ
Literature review reveals that tin oxide has been extensively used in lithium ion batteries. Interestingly, unlike SnO2 based LIBs electrodes which exhibit sharp capacity decay due to large volume expansion of tin oxide, is not seen in our MIBs. Thus, SnO2 based electrodes were further used for Mg2+/Li+ hybrid ion batteries as shown in Fig. S6(b)–(d). To examine the ultrafast charging/discharging capabilities of TO and TO-rGO1 electrodes, hybrid cells were cycled at current densities ranging from 20 to 1000 mA/g. Fig. S6(b) shows the rate capability where discharge capacities of 260 and 350 mAh/g were exhibited by pure TO and TO-rGO1, respectively at 20 mA/g. Increase in applied current density reduced the discharge capacities of both materials. The discharge capacity of 268 mAh/g can be measured when the current density reduces back to 20 mA/g, which indicates a high stability as well as excellent reversibility of TO-rGO1. The Galvanostatic charge/discharge profiles of TO-rGO1 composite at various current densities are shown in Fig. S6(c). Noticeably, the improved rate capability and specific capacity of TO-rGO1 composite compared with pristine TO is because the coating of SnO2 nanoparticles by rGO sheets protects the nanoparticles from severe structural degradation during lithiation/delithiation. Furthermore, rGO nanosheets improve the electrical conductivity of SnO2 nanoparticles, which ultimately boost up electron transportation during redox reactions. The cycle stability profiles of pure TO and TO-rGO1 at 100 mA/g current density are shown in Fig. S6(d). It can be seen that TO-rGO1 based MLIB cell reveal the specific capacity of 160 and 131 mAh/g after 50 and 100 cycles. The electrochemical impedance spectroscopic (EIS) study is carried out on fully activated MIB half-cells as shown in Fig. 6(b). The equivalent circuit shown in Fig. S7 describes the electrochemical reaction steps. It contains bulk resistance Rb (electrolyte, electrodes, and separator), electron transfer resistance Re or capacitance CPEe at SEI and Mg2+ ion diffusion resistance Ri or capacitance CPEi, in high and low frequency regions. W1 is Warburg impedance representing Mg2+ diffusion inside the cathode. The Z-view software was used to evaluate the EIS data. Careful observation revealed that TO-rGO1 and TO-rGO2 composites with high electrical conductivities exhibited the lower resistance values (900 and 809 Ohm) compared with bare TO cathode as shown in Fig. 6(b). The inset of Fig. 6(b) shows the plot between Z’ and x-1/2 in low frequency region, where x is angular frequency
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
8
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
Fig. 6. (a) Comparison of the specific capacities between TO-rGO2 (present work) and other reported Mg-storage cathode materials [28,51–54], (b) Nyquist plots with inset showing plot between Z’ and x-1/2 in low frequency region (Frequency range: 106–0.01 Hz), Ex-situ XRD profiles of (c) TO, and (d) TO-rGO2 cycled in APC electrolytes at different charge stages.
Table 1 Comparison of present work with previously reported rGO based composites in magnesium ion batteries. Composites
System
Capacity Improvement (%)
Capacity Retention (%) [Cycles]
References
FeVO40.9H2O/Graphene V2O5 nH2O@rGO Mn3O4/GO Mn3O4/rGO Bi/rGO MgMn2O4/rGO TO-rGO2
Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion Mg-ion
18.91 64.15 54.67 58.13 21.68 38.01 45.45
90 81 95 96 88 74 98
[17] [40] [41] [41] [42] [43] Present Work
(x = 2pf). The low gradient slopes of both composites indicated the higher Mg2+ ion diffusivity in the TO-rGO1 and TO-rGO2 structures compared to that of bare TO structure. Thus, faster electrochemical kinetics promoted the specific capacities of both composites [49]. Ex-situ XRD is used to investigate the effect of charge states on TO or TO-rGO2 composite structures during insertion/extraction of Mg2+ ions. For this purpose, the electrodes (TO or TO-rGO2) were cycled at 100 mA/g in APC/APC-LiCl electrolytes and then charged/discharged to the desired potentials. Ex-situ XRD profile of TO or TO-rGO2 powders reveals strong peaks at two theta equal to 26.50, 33.63, 37.85, and 51.52°. On the other hand, assembled electrode reveals only two distinct peaks at two theta equal to 33.63 and 51.52° corresponding to active material as shown in Fig. 6 (c-d). It can be seen that pristine electrode or charged TO electrodes reveal the distinct peaks at two theta equal to 33.63 and 51.52° as shown in Fig. 6(c). When the TO electrode is discharged in APC electrolytes to 1.0 or 0.0 V, the peaks at 33.63° and 51.52° shift towards higher angles, which is attributed to insertion of Mg2+ ions inside the TO lattices. These changes correlate the fast kinetics and variations in the lattice parameters of tin oxide during insertion/extraction of Mg2+ ions [46]. In case of TOrGO2 electrode (Fig. 6(d)), the distinct peaks at two theta equal
[50] [200] [20] [700] [50] [1000] [150]
to 33.63 and 51.52° corresponding to active material also shift towards higher angles. However, the changes in peak positions were not significant in case of TO-rGO2 cathode. This might be attributed to the presence of graphene sheets around the tin oxide nanoparticles, which facilitates the surface charge storage instead of diffusion inside the tin oxide lattices [28,37]. However, detailed process is still unknown due to lack of interfacial studies in this area. Additionally, ex-situ XRD study for TO-rGO1 electrode cycled in APC-LiCl electrolyte is also carried out as shown in Fig. S8. However, peaks related to active material were not observed after cycling. This is because SnO2 is covered by an unstable solid electrolyte interphase (SEI), which blocks the passage of ions during cycling process thus leading to rapid capacity decay as discussed in electrochemical characterization part. The same phenomenon was also observed during the lithiation of tin oxides nanowires in previous works [50]. SEM equipped with EDS is used to examine the microstructural changes before and after cycling in Mg2+ and Mg2+/Li+ hybrid electrolytes as shown in Fig. 7. It can be seen that TO-rGO1 electrode displays the SnO2 nanoparticles with 50 nm size embedded uniformly in graphene nanosheets (Fig. 7(a)). The corresponding EDS profile confirms the presence of SnO2 nanoparticles, carbon black,
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
9
Fig. 7. (a) Freshly prepared TO-rGO1 electrode, (b) EDS of selected area in (a); (c) TO-rGO1 electrode cycled in APC electrolytes, (d) EDS of selected area in (c); (e) TO-rGO1 electrode cycled in APC-LiCl electrolytes and (f) EDS of selected area in (e) (insets show high magnification images).
and binder as shown by peaks (Fig. 7(b)). The electrodes were cycled in APC and APC-LiCl electrolytes for about 100 cycles and examined in charged states. The SEM of electrode cycled in APC electrolyte reveals increase in particle size of SnO2 nanoparticles, which is about 85 nm as shown in Fig. 7(c). However, the volume expansion is not as high as observed in LIBs (~250%). Thus, SnO2 is promising anode materials for MIBs with stable SEI and shows long cycle life as discussed in electrochemical characterization parts. The EDS of selected part shows the presence of additional peaks corresponding to Mg as shown in Fig. 7(d), which might be due to trapping of some Mg2+ and is consistent with previous work [28,47,55]. Fig. 7(e) shows the morphology of electrode cycled in APC-LiCl electrolyte, where swear volume expansion of SnO2 and unstable SEI (due to presence of LiCl) can be clearly seen in magnified image. This is because crystalline SnO2 nanoparticles decrystallize and agglomerate into large volume globules, which ultimately fracture during cycling [28,37,56]. Therefore, loss of
electrical integrity of electrodes leads to rapid capacity fading during charging/discharging process. 4. Conclusions To summarize, we have presented a new strategy to synthesize SnO2-rGO composites at low temperature via electrostatic-interac tion-induced self-assembly approach. The synthesized composites are tested as electrode materials for Mg and Mg/Li hybrid ion batteries. Interestingly, no volume expansion of SnO2 nanoparticles was observed during magnesiation and de-magnesiation. The MIB cells exhibited the maximum specific capacity of 222 mAh/g at a current density of 20 mA/g and excellent capacity retentions (90.05%). Furthermore, co-intercalation of Mg2+ and Li+ ions revealed a maximum specific capacity of 350 mAh/g at a current density of 20 mA/g. However, capacity retentions of MLIBs are not as good as for MIB, which is attributed to volume expansion
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
10
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx
of SnO2 nanoparticles due to presence of LiCl. Additionally, effect of cut-off voltages, ex-situ XRD, and EIS studies were carried out to understand the basic electrochemical mechanism. This study establishes that tin oxide encapsulated in rGO is a promising candidate for high-performance and potentially safe MIB cathodes. Author contributions Muhammad Asif and Muhammad Rashad performed the experiments, analyzed the data, wrote the initial manuscript draft and finalized the manuscript for submission on equal contribution basis. Jafar Hussain Shah and Syed Danish Ali Zaidi participated in discussions of the results. All authors have reviewed the manuscript. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgement This research was supported by National Natural Science Foundation of China (51601073), Jiangsu Distinguished Professor Project (1064901601), Jiangsu Provincial Six Talent Peaks Project (1062991801), and Jiangsu University of Science and Technology Research Start-Up Fund (1062921905). Appendix A. Supplementary material Supplementary data to this article can be found online at https://doi.org/10.1016/j.jcis.2019.11.064. References [1] V. Etacheri, R. Marom, R. Elazari, G. Salitra, D. Aurbach, Challenges in the development of advanced Li-ion batteries: a review, Energy Environ. Sci. 4 (9) (2011) 3243–3262, https://doi.org/10.1039/C1EE01598B. [2] A. Manthiram, Materials challenges and opportunities of lithium ion batteries, J. Phys. Chem. Lett. 2 (3) (2011) 176–184, https://doi.org/10.1021/jz1015422. [3] Z. Sun, J. Zhang, L. Yin, G. Hu, R. Fang, H.-M. Cheng, F. Li, Conductive porous vanadium nitride/graphene composite as chemical anchor of polysulfides for lithium-sulfur batteries, Nat. Commun. 8 (2017) 14627, https://doi.org/ 10.1038/ncomms14627. [4] J. Muldoon, C.B. Bucur, T. Gregory, Quest for nonaqueous multivalent secondary batteries: magnesium and beyond, Chem. Rev. 114 (23) (2014) 11683–11720, https://doi.org/10.1021/cr500049y. [5] M. Rashad, F. Pan, Z. Yu, M. Asif, H. Lin, R. Pan, Investigation on microstructural, mechanical and electrochemical properties of aluminum composites reinforced with graphene nanoplatelets, Prog. Natl. Sci.: Mater. Int. 25 (5) (2015) 460–470, https://doi.org/10.1016/j.pnsc.2015.09.005. [6] P. Saha, M.K. Datta, O.I. Velikokhatnyi, A. Manivannan, D. Alman, P.N. Kumta, Rechargeable magnesium battery: current status and key challenges for the future, Prog. Mater Sci. 66 (2014) 1–86, https://doi.org/10.1016/j.pmatsci. 2014.04.001. [7] M.M. Huie, D.C. Bock, E.S. Takeuchi, A.C. Marschilok, K.J. Takeuchi, Cathode materials for magnesium and magnesium-ion based batteries, Coord. Chem. Rev. 287 (2015) 15–27, https://doi.org/10.1016/j.ccr.2014.11.005. [8] O. Tutusaus, R. Mohtadi, N. Singh, T.S. Arthur, F. Mizuno, Study of electrochemical phenomena observed at the Mg metal/electrolyte interface, ACS Energy Lett. 2 (1) (2017) 224–229, https://doi.org/10.1021/acsenergy lett.6b00549. [9] T.D. Gregory, R.J. Hoffman, R.C. Winterton, Nonaqueous electrochemistry of magnesium: applications to energy storage, J. Electrochem. Soc. 137 (3) (1990) 775–780, https://doi.org/10.1149/1.2086553. [10] D. Aurbach, Y. Gofer, A. Schechter, O. Chusid, H. Gizbar, Y. Cohen, M. Moshkovich, R. Turgeman, A comparison between the electrochemical behavior of reversible magnesium and lithium electrodes, J. Power Sources 97–98 (2001) 269–273, https://doi.org/10.1016/S0378-7753(01)00622-X. [11] D. Aurbach, Z. Lu, A. Schechter, Y. Gofer, H. Gizbar, R. Turgeman, Y. Cohen, M. Moshkovich, E. Levi, Prototype systems for rechargeable magnesium batteries, Nature 407 (2000) 724, https://doi.org/10.1038/35037553.
[12] R. Zhang, X. Yu, K.-W. Nam, C. Ling, T.S. Arthur, W. Song, A.M. Knapp, S.N. Ehrlich, X.-Q. Yang, M. Matsui, a-MnO2 as a cathode material for rechargeable Mg batteries, Electrochem. Commun. 23 (2012) 110–113, https://doi.org/ 10.1016/j.elecom.2012.07.021. [13] L. Wang, K. Asheim, P.E. Vullum, A.M. Svensson, F. Vullum-Bruer, Sponge-like porous manganese(II, III) oxide as a highly efficient cathode material for rechargeable magnesium ion batteries, Chem. Mater. 28 (18) (2016) 6459– 6470, https://doi.org/10.1021/acs.chemmater.6b01016. [14] H. Zhang, K. Ye, X. Huang, X. Wang, K. Cheng, X. Xiao, G. Wang, D. Cao, Preparation of Mg1.1Mn6O124.5H2O with nanobelt structure and its application in aqueous magnesium-ion battery, J. Power Sources 338 (2017) 136–144, https://doi.org/10.1016/j.jpowsour.2016.10.078. [15] J. Yin, A.B. Brady, E.S. Takeuchi, A.C. Marschilok, K.J. Takeuchi, Magnesium-ion battery-relevant electrochemistry of MgMn2O4: crystallite size effects and the notable role of electrolyte water content, Chem. Commun. 53 (26) (2017) 3665–3668, https://doi.org/10.1039/C7CC00265C. [16] Q.D. Truong, M. Kempaiah Devaraju, P.D. Tran, Y. Gambe, K. Nayuki, Y. Sasaki, I. Honma, Unravelling the surface structure of MgMn2O4 cathode materials for rechargeable magnesium-ion battery, Chem. Mater. 29 (15) (2017) 6245– 6251, https://doi.org/10.1021/acs.chemmater.7b01252. [17] H. Zhang, K. Ye, K. Zhu, R. Cang, J. Yan, K. Cheng, G. Wang, D. Cao, The FeVO40.9H2O/Graphene composite as anode in aqueous magnesium ion battery, Electrochim. Acta 256 (2017) 357–364, https://doi.org/10.1016/ j.electacta.2017.10.038. [18] S. Tepavcevic, Y. Liu, D. Zhou, B. Lai, J. Maser, X. Zuo, H. Chan, P. Král, C.S. Johnson, V. Stamenkovic, N.M. Markovic, T. Rajh, Nanostructured layered cathode for rechargeable Mg-ion batteries, ACS Nano 9 (8) (2015) 8194–8205, https://doi.org/10.1021/acsnano.5b02450. [19] Y. Cheng, Y. Shao, V. Raju, X. Ji, B.L. Mehdi, K.S. Han, M.H. Engelhard, G. Li, N.D. Browning, K.T. Mueller, J. Liu, Molecular storage of Mg ions with vanadium oxide nanoclusters, Adv. Funct. Mater. 26 (20) (2016) 3446–3453, https://doi. org/10.1002/adfm.201505501. [20] Z.-L. Tao, L.-N. Xu, X.-L. Gou, J. Chen, H.-T. Yuan, TiS2 nanotubes as the cathode materials of Mg-ion batteries, Chem. Commun. 18 (2004) 2080–2081, https:// doi.org/10.1039/B403855J. [21] X. Sun, V. Duffort, B.L. Mehdi, N.D. Browning, L.F. Nazar, Investigation of the mechanism of Mg insertion in birnessite in nonaqueous and aqueous rechargeable Mg-ion batteries, Chem. Mater. 28 (2) (2016) 534–542, https:// doi.org/10.1021/acs.chemmater.5b03983. [22] Y. Gu, Y. Katsura, T. Yoshino, H. Takagi, K. Taniguchi, Rechargeable magnesium-ion battery based on a TiSe2-cathode with d-p orbital hybridized electronic structure, Sci. Rep. 5 (2015) 12486, https://doi.org/ 10.1038/srep12486 https://www.nature.com/articles/srep12486#supplementaryinformation. [23] X. Sun, V. Duffort, L.F. Nazar, Prussian blue MgLi hybrid batteries, Adv. Sci. 3 (8) (2016), https://doi.org/10.1002/advs.201600044. 1600044-n/a. [24] R.Y. Wang, C.D. Wessells, R.A. Huggins, Y. Cui, Highly reversible open framework nanoscale electrodes for divalent ion batteries, Nano Lett. 13 (11) (2013) 5748–5752, https://doi.org/10.1021/nl403669a. [25] T. Koketsu, J. Ma, B.J. Morgan, M. Body, C. Legein, W. Dachraoui, M. Giannini, A. Demortière, M. Salanne, F. Dardoize, H. Groult, O.J. Borkiewicz, K.W. Chapman, P. Strasser, D. Dambournet, Reversible magnesium and aluminium ions insertion in cation-deficient anatase TiO2, Nat. Mater. 16 (2017) 1142, https://doi.org/10.1038/nmat4976. [26] X. Bian, Y. Gao, Q. Fu, S. Indris, Y. Ju, Y. Meng, F. Du, N. Bramnik, H. Ehrenberg, Y. Wei, A long cycle-life and high safety Na+/Mg2+ hybrid-ion battery built by using a TiS2 derived titanium sulfide cathode, J. Mater. Chem. A 5 (2) (2017) 600–608, https://doi.org/10.1039/C6TA08505A. [27] A.M. Dimiev, J.M. Tour, Mechanism of graphene oxide formation, ACS Nano 8 (3) (2014) 3060–3068, https://doi.org/10.1021/nn500606a. [28] M. Rashad, H. Zhang, M. Asif, K. Feng, X. Li, H. Zhang, Low-cost roomtemperature synthesis of NaV3O81.69H2O nanobelts for Mg batteries, ACS Appl. Mater. Interfaces 10 (5) (2018) 4757–4766, https://doi.org/10.1021/ acsami.7b18682. [29] K. Krishnamoorthy, M. Veerapandian, K. Yun, S.J. Kim, The chemical and structural analysis of graphene oxide with different degrees of oxidation, Carbon 53 (2013) 38–49, https://doi.org/10.1016/j.carbon. 2012.10.013. [30] S.A.A. Aziz, S.H. Amirnordin, H.A. Rahman, H.Z. Abdullah, H. Taib, Effect of zeta potential of stanum oxide (SnO2) on electrophoretic deposition (EPD) on porous alumina, Adv. Mater. Res. 795 (2013) 334–337. [31] M. Rashad, h. zhang, X. Li, H. Zhang, Fast kinetics of Mg2+/Li+ hybrid ions in polyanion Li3V2(PO4)3 cathode in wide temperature range, J. Mater. Chem. A (2019), https://doi.org/10.1039/C9TA00502A. [32] Y. Cheng, L.R. Parent, Y. Shao, C. Wang, V.L. Sprenkle, G. Li, J. Liu, Facile synthesis of chevrel phase nanocubes and their applications for multivalent energy storage, Chem. Mater. 26 (17) (2014) 4904–4907, https://doi.org/ 10.1021/cm502306c. [33] Z. Zhang, H. Xu, Z. Cui, P. Hu, J. Chai, H. Du, J. He, J. Zhang, X. Zhou, P. Han, G. Cui, L. Chen, High energy density hybrid Mg2+/Li+ battery with superior ultralow temperature performance, J. Mater. Chem. A 4 (6) (2016) 2277–2285, https://doi.org/10.1039/C5TA09591C. [34] H.-S. Kim, J.B. Cook, H. Lin, Jesse S. Ko, Sarah H. Tolbert, V. Ozolins, B. Dunn, Oxygen vacancies enhance pseudocapacitive charge storage properties of MoO3x, Nat. Mater. 16 (2016) 454, https://doi.org/ 10.1038/nmat4810.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064
M. Asif et al. / Journal of Colloid and Interface Science xxx (xxxx) xxx [35] J. Wang, J. Polleux, J. Lim, B. Dunn, Pseudocapacitive contributions to electrochemical energy storage in TiO2 (Anatase) nanoparticles, J. Phys. Chem. C 111 (40) (2007) 14925–14931, https://doi.org/10.1021/ jp074464w. [36] X. Xie, M.-Q. Zhao, B. Anasori, K. Maleski, C.E. Ren, J. Li, B.W. Byles, E. Pomerantseva, G. Wang, Y. Gogotsi, Porous heterostructured MXene/carbon nanotube composite paper with high volumetric capacity for sodium-based energy storage devices, Nano Energy 26 (2016) 513–523, https://doi.org/ 10.1016/j.nanoen.2016.06.005. [37] Y. Dong, Z. Zhao, Z. Wang, Y. Liu, X. Wang, J. Qiu, Dually fixed SnO2 nanoparticles on graphene nanosheets by polyaniline coating for superior lithium storage, ACS Appl. Mater. Interfaces 7 (4) (2015) 2444–2451, https:// doi.org/10.1021/am506818h. [38] S.D. Perera, R.B. Archer, C.A. Damin, R. Mendoza-Cruz, C.P. Rhodes, Controlling interlayer interactions in vanadium pentoxide-poly(ethylene oxide) nanocomposites for enhanced magnesium-ion charge transport and storage, J. Power Sources 343 (2017) 580–591, https://doi.org/10.1016/j.jpowsour. 2017.01.052. [39] X. Sun, P. Bonnick, L.F. Nazar, Layered TiS2 positive electrode for Mg batteries, ACS Energy Lett. 1 (1) (2016) 297–301, https://doi.org/10.1021/ acsenergylett.6b00145. [40] Q. An, Y. Li, H. Deog Yoo, S. Chen, Q. Ru, L. Mai, Y. Yao, Graphene decorated vanadium oxide nanowire aerogel for long-cycle-life magnesium battery cathodes, Nano Energy 18 (2015) 265–272, https://doi.org/10.1016/ j.nanoen.2015.10.029. [41] L. Wang, P.E. Vullum, K. Asheim, X. Wang, A.M. Svensson, F. Vullum-Bruer, High capacity Mg batteries based on surface-controlled electrochemical reactions, Nano Energy 48 (2018) 227–237, https://doi.org/10.1016/ j.nanoen.2018.03.061. [42] T.R. Penki, G. Valurouthu, S. Shivakumara, V.A. Sethuraman, N. Munichandraiah, In situ synthesis of bismuth (Bi)/reduced graphene oxide (RGO) nanocomposites as high-capacity anode materials for a Mg-ion battery, New J. Chem. 42 (8) (2018) 5996–6004, https://doi.org/10.1039/C7NJ04930G. [43] G. Liu, Q. Chi, Y. Zhang, Q. Chen, C. Zhang, K. Zhu, D. Cao, Superior high rate capability of MgMn2O4/rGO nanocomposites as cathode materials for aqueous rechargeable magnesium ion batteries, Chem. Commun. 54 (68) (2018) 9474– 9477, https://doi.org/10.1039/C8CC05366A. [44] L.N. Zhang Changhuan, Yao Hurong, Liu Lin, Yin Yaxia, Guo Yuguo, Synthesis of Sn nanoparticles/graphenenanosheet hybrid electrode material with threedimensional conducting network for magnesium storage, Acta Chim. Sinica 75 (2017) 206–211, https://doi.org/10.6023/A16100542. [45] X. Ou, X. Liang, F. Zheng, P. Wu, Q. Pan, X. Xiong, C. Yang, M. Liu, In situ X-ray diffraction investigation of CoSe2 anode for Na-ion storage: Effect of cut-off
[46]
[47]
[48]
[49]
[50]
[51]
[52]
[53]
[54]
[55]
[56]
11
voltage on cycling stability, Electrochim. Acta 258 (2017) 1387–1396, https:// doi.org/10.1016/j.electacta.2017.11.198. M. Rashad, X. Li, H. Zhang, Magnesium/lithium-ion hybrid battery with high reversibility by employing NaV3O81.69H2O nanobelts as a positive electrode, ACS Appl. Mater. Interfaces 10 (25) (2018) 21313–21320, https://doi.org/ 10.1021/acsami.8b04139. M. Asif, M. Rashad, Z. Ali, H. Qiu, W. Li, L. Pan, Y. Hou, Ni-doped MnO2/CNT nanoarchitectures as a cathode material for ultra-long life magnesium/lithium hybrid ion batteries, Mater. Today Energy 10 (2018) 108–117, https://doi.org/ 10.1016/j.mtener.2018.08.010. E. Frackowiak, F. Béguin, Electrochemical storage of energy in carbon nanotubes and nanostructured carbons, Carbon 40 (10) (2002) 1775–1787, https://doi.org/10.1016/S0008-6223(02)00045-3. J.H. Choi, S.-K. Park, Y.C. Kang, A salt-templated strategy toward hollow iron selenides-graphitic carbon composite microspheres with interconnected multicavities as high-performance anode materials for sodium-ion batteries, Small 15 (2) (2019) 1803043, https://doi.org/10.1002/smll.201803043. J.Y. Huang, L. Zhong, C.M. Wang, J.P. Sullivan, W. Xu, L.Q. Zhang, S.X. Mao, N.S. Hudak, X.H. Liu, A. Subramanian, H. Fan, In situ observation of the electrochemical lithiation of a single SnO2 nanowire electrode, Science 330 (6010) (2010) 1515–1520, https://doi.org/10.1126/science.1195628. X. Deng, Y. Xu, Q. An, F. Xiong, S. Tan, L. Wu, L. Mai, Manganese ion preintercalated hydrated vanadium oxide as a high-performance cathode for magnesium ion batteries, J. Mater. Chem. A 7 (17) (2019) 10644–10650, https://doi.org/10.1039/C8TA11236C. F. Liu, Y. Liu, X. Zhao, X. Liu, L.-Z. Fan, Pursuit of a high-capacity and long-life Mg-storage cathode by tailoring sandwich-structured MXene@carbon nanosphere composites, J. Mater. Chem. A (2019), https://doi.org/10.1039/ C9TA02212K. K. Liang, K. Marcus, L. Guo, Z. Li, L. Zhou, Y. Li, S.T. De Oliveira, N. Orlovskaya, Y. H. Sohn, Y. Yang, A freestanding NiSx porous film as a binder-free electrode for Mg-ion batteries, Chem. Commun. 53 (54) (2017) 7608–7611, https://doi.org/ 10.1039/C7CC03517A. Y. Meng, D. Wang, Y. Zhao, R. Lian, Y. Wei, X. Bian, Y. Gao, F. Du, B. Liu, G. Chen, Ultrathin TiO2-B nanowires as an anode material for Mg-ion batteries based on a surface Mg storage mechanism, Nanoscale 9 (35) (2017) 12934–12940, https://doi.org/10.1039/C7NR03493H. M. Rashad, M. Asif, Y. Wang, Z. He, I. Ahmed, Recent advances in electrolytes and cathode materials for magnesium and hybrid-ion batteries, Energy Storage Mater. (2019), https://doi.org/10.1016/j.ensm.2019.10.004. M. Rashad, H. Zhang, X. Li, H. Zhang, Fast kinetics of Mg2+/Li+ hybrid ions in a polyanion Li3V2(PO4)3 cathode in a wide temperature range, J. Mater. Chem. A 7 (16) (2019) 9968–9976, https://doi.org/10.1039/C9TA00502A.
Please cite this article as: M. Asif, M. Rashad, J. H. Shah et al., Surface modification of tin oxide through reduced graphene oxide as a highly efficient cathode material for magnesium-ion batteries, Journal of Colloid and Interface Science, https://doi.org/10.1016/j.jcis.2019.11.064