Bundled and dispersed carbon nanotube assemblies on graphite superstructures as free-standing lithium-ion battery anodes

Accepted Manuscript Bundled and dispersed carbon nanotube assemblies on graphite superstructures as free-standing lithium-ion battery anodes Yiran Yan, Changling Li, Chueh Liu, Zafer Mutlu, Bo Dong, Jingjing Liu, Cengiz S. Ozkan, Mihrimah Ozkan PII:

S0008-6223(18)30959-X

DOI:

10.1016/j.carbon.2018.10.044

Reference:

CARBON 13562

To appear in:

Carbon

Received Date: 8 July 2018 Revised Date:

29 September 2018

Accepted Date: 12 October 2018

Please cite this article as: Y. Yan, C. Li, C. Liu, Z. Mutlu, B. Dong, J. Liu, C.S. Ozkan, M. Ozkan, Bundled and dispersed carbon nanotube assemblies on graphite superstructures as free-standing lithium-ion battery anodes, Carbon (2018), doi: https://doi.org/10.1016/j.carbon.2018.10.044. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT

CNT Bundles on Graphite

CNTs on Graphite Foam

M AN U Dispersed CNTs on Graphite

An ne a

lin g

TE D

200 nm

EP

W ith

g lin a ne n A

AC C

No

SC

RI PT

50 nm

200 nm

ACCEPTED MANUSCRIPT

Bundled and Dispersed Carbon Nanotube Assemblies on Graphite Superstructures as FreeStanding Lithium-Ion Battery Anodes†

Mihrimah Ozkan*c

RI PT

Yiran Yan,a,‡ Changling Li,a,‡ Chueh Liu,a Zafer Mutlu,b Bo Dong,c Jingjing Liu,a Cengiz S. Ozkan*a and

aMaterials Science and Engineering Program, Department of Mechanical Engineering, University of

SC

California Riverside, CA 92521 (USA).

94720, USA

M AN U

bDepartment of Electrical Engineering and Computer Science, University of California, Berkeley, CA

cDepartment of Electrical and Computer Engineering, Department of Chemistry, University of California, Riverside, CA 92521 (USA).

AC C

EP

TE D

‡These authors contributed equally to this work.

*Corresponding authors. Telephone number: (951) 827-2417. Emails: Cengiz S. Ozkan ([email protected]) and Mihrimah Ozkan ([email protected])

1

ACCEPTED MANUSCRIPT

Abstract Carbonaceous materials are intensively used as additives or active electrode materials in lithium-ion battery (LIB) industry due to their stable chemical and physical properties. Compared to

RI PT

developing next-generation high-capacity non-carbonaceous anode materials, improvement on current carbonaceous materials could lead to instant commercial values due to less process modifications to the battery manufacturing. Here, we report a facile approach to synthesize carbon nanotubes (CNTs) with

SC

controlled assemblies: well-dispersed CNTs vs. bundled CNTs. Furthermore, we incorporated these carbon nanotubes onto three-dimensional (3D) graphite foams as free-standing anodes for lithium-ion

M AN U

batteries. This hierarchical 3D network provided high surface area and ultra-high conductivity with enhanced battery capacity. With controlled growth conditions, the assembly of CNTs can be changed from bundled state to dispersed state, resulting in a significant improvement in electrochemical performance. The dispersed CNTs showed a higher specific capacity of above 800 ℎ

over 120

. The loose structure of well-

TE D

cycles, while CNT bundles exhibited a specific capacity of 500

ℎ

dispersed CNTs provides sufficient active interfaces between electrolyte and materials, as well as shortened ion transport path. Insights can be gained in improving state-of-the-art battery performance

AC C

EP

by controlling the bulk assemblies of CNT additives.

2

ACCEPTED MANUSCRIPT

1. Introduction The increasing demand for portable electronic devices and electric vehicles are pushing the development of high performance batteries, in particular lithium ion batteries (LIBs), to have higher

RI PT

capacity, higher loading and lower cost [1-3]. Tremendous efforts have been made on exploring the next-generation electrode materials for lithium ion batteries with innovative architectures, nanostructured morphologies, advanced electrolyte, etc. [4-6]. Extensive work has been made in

SC

developing next-generation energy storage devices such as lithium-ion batteries with electrodes using silicon [7, 8], germanium [9, 10], metal oxide [11, 12], air [13-15], hybrid materials [16-19], as well as

M AN U

other metal-ion batteries [20, 21]. It is also important and necessary to optimize concurrent commercialized materials. For example, carbon-based anodes, with high reliability and stable cycling performance, have already demonstrated its commercial value [22-26]. It has been utilized in commercial lithium-ion batteries for decades either as additives or active electrode materials with

TE D

numerous advantages including: high electrochemical stability, relatively high capacity, low volumetric expansion during charge/discharge, earth abundancy and low cost [27-32]. Researchers have demonstrated that micro/nanostructured carbonaceous materials are now being

EP

widely studied and used for electrochemical device applications [32, 33]. Besides the commercial graphite, three-dimensional metal-organic frameworks (MOFs) and porous carbon structures have been

AC C

reported as excellent anode materials [34-36]. One dimensional (1D) carbon nanotubes and two dimensional (2D) graphene have been largely applied into electrochemical devices with superior performance [37-42]. For example, carbon nanotubes have been largely reported as active anode materials or additives to other inorganic anode materials for higher performing LIBs with capacities up to 1000

ℎ

[37, 43].

3

ACCEPTED MANUSCRIPT

Integrating above carbonaceous materials into 3D hybrid micro/nanostructure to form 3D superstructures can be an economic and high performing alternative to replace the commercially used pure carbon in LIB anodes [44]. These hybrid 3D superstructures provide large surface area as reaction

RI PT

sites, high conductivity, as well as superior adaptation for expansion during cycles of charge and discharge [37, 45]. For example, Vinayan and coworkers have reported a hybrid superstructure of CNTs and graphene that showed nearly four times higher specific capacity compared with pure graphene [46].

above 400

ℎ

SC

Also, a self-templated porous carbon and CNTs nanostructure developed by Guo et al. has showed at rate of 1 C. Therefore, it is important to explore the merits of CNTs and 3D

M AN U

hierarchical structure in order to achieve optimum LIB performance with high active materials loading. In this work, we present a 3D superstructure composed of carbon nanotubes and 3D graphite foam that can be used as free-standing lithium ion battery anodes. Chemical vapor deposition (CVD) was chosen to grow carbon nanotubes directly on 3D graphite foam with controlled properties.

TE D

Typically, vertically-aligned carbon nanotubes (or carbon nanotube forest) were obtained at short growth time (~5 min) [47]. For LIB applications, larger mass loading of CNTs was preferred but the increased CVD growth time would lead to agglomerated CNTs (bundled state). We introduced an

EP

annealing step to tune the bulk assemblies of CNTs from bundled state to well-dispersed state, resulting in a significant improvement in electrochemical performance. In the CVD process, we used nickel

AC C

catalyst grown on graphite foam templated from commercial Ni foam to grow CNTs. By introducing an annealing process, we created nickel nanoislands that served as discrete catalytic sites to grow welldispersed CNTs. As a result, we were able to obtain two configurations of CNTs (bundled state vs. welldispersed state) on graphite substrates with diameter less than 40 nm. Both types of assemblies showed enhanced capacity compared to commercial carbon-based electrode materials, and the well-dispersed CNTs on graphite showed higher electrochemical performance than the bundled ones. The specific

4

ACCEPTED MANUSCRIPT

energy storage capacity of these 3D superstructures almost tripled to that of commercial graphite due to the increased materials conductivity, higher Li-ion storage sites and more robust electrode integrity. The fabrication process was simple, which only involved chemical vapor deposition and acid etching,

RI PT

without the traditional additives of binders and heavy current collectors. The production of such hybrid structure was cost-efficient and highly scalable. We realized that the bulk assemblies of carbon nanotubes could be a crucial parameter in optimizing carbon-based materials as LIB anodes.

SC

2. Experimental section 2.1 Materials synthesis

M AN U

Nickel foam sheets (~346 g/m2 in areal density, ~1.6 mm in thickness, and purity > 99.99%) were cut into disks of 16 mm diameter and placed in a conventional single-zone horizontal quartz tube (50 mm) furnace. The tube furnace was pumped down to remove the air and then filled with argon gas (100 sccm) and hydrogen gas (200 sccm) to 670 torr. The center of heating zone was heated to 705 °C

TE D

with a ramping rate of 30 °C/min. Then 10 sccm of ethylene gas was introduced into the reaction tube, and the tube furnace was kept at 750 °C for 60 min. Finally, the tube furnace was naturally cooled to room temperature under argon (100 sccm) and hydrogen (50 sccm) environment. The samples were

EP

removed from the furnace and immersed into a hydrochloric acid (HCl, 15 wt%) solution for approximately 48 hours to completely dissolve the Ni, obtaining the free-standing 3D graphite foams. In

AC C

the next step, we first deposited approximately 4 nm of the Ni catalyst film onto the as-grown graphite foam sheets via the e-beam evaporator with a deposition rate of 0.5 Å/min, and then placed the samples into the same furnace. The furnace was pumped down to remove the air and then filled with argon (400 sccm) and hydrogen (50 sccm) to 700 torr. The center of heating zone was heated to 700 oC with a ramping rate of 45 oC/min and kept at this temperature for 30 min to ensure the formation Ni nanoislands. Ethylene gas (50 sccm) was then introduced into the reaction tube, and the tube furnace

5

ACCEPTED MANUSCRIPT

was kept at 700 °C for another 30 min, followed by natural cooling to room temperature. The weight of 3D graphite foam was between 7-8 mg. We kept the weight percent of CNTs to be ~10% of the graphite foam weight, which was about 0.7-0.8 mg. Finally, the samples were treated with concentrated nitric

RI PT

acid (HNO3) at 250 °C for 1-3 h to attach functional groups and increase the wettability of the composite electrode. 2.2 Materials characterization

SC

The microstructural characterizations were done by scanning electron microscopy (SEM, FEI NNS450) and transmission electron microscope (TEM, Titan Themis 300). The crystal structures were

M AN U

examined by X-ray diffraction (XRD, PANalytical Empyrean) with Cu-Kα radiation. Raman spectra were collected using a Horiba system with a 532 nm excitation laser (<2 mW excitation power, 100× objective lens). Micromeritics TriStar II 3020 was used to perform the nitrogen adsorption isotherm (77 K) measurements of the CNTs/graphite composites. The surface areas of CNTs/graphite composites

TE D

were determined using the Brunauer-Emmett-Teller (BET) model. The pore sizes were calculated using the Barret-Joyner-Halenda (BJH) model. 2.3 Electrochemical characterization

EP

Battery assembly was performed by using a button-type (CR 2032) two-electrode half-cell configuration in an argon-filled VAC Omni-lab glovebox with oxygen and H2O level below 1 ppm.

AC C

Electrolyte solution of 1 M LiPF6 salt in FEC/DMC 1:4 by weight was prepared and used with a pure lithium metal plate as the counter electrode and a Celgard 3501 porous PP membrane as the separator. Electrochemical performance and galvanostatic charge/discharge were performed on Arbin BT300 with a voltage window ranging from 0.01 to 3.0 V (vs. Li+/Li). Electrochemical impedance spectroscopy (EIS) experiments were conducted using the Biologic VMP. 3. Results and discussion

6

ACCEPTED MANUSCRIPT

3.1 The preparation of carbon nanotube-graphite 3D hybrid structure The fabrication process of carbon nanotube-graphite 3D hybrid structure is illustrated in Fig. 1.

RI PT

Commercial nickel foam was used as the 3D scaffold for graphite growth (Fig. 1a). The graphite foam was synthesized by precipitation of a very thin layer of graphite on the Ni foam at 750 °C by using ethylene as a carbon source. Then nickel scaffold was then etched by hydrochloric acid, resulting in a

SC

3D graphite foam (Fig. 1b). Optical and scanning electron microscope images of nickel foam and graphite foam were shown in Fig. S1(a-d). In this process, the nickel foam was saturated with carbon at

M AN U

high temperature and most of the carbon will precipitate at the surface of the nickel foam during the cooling, forming continuous layers of graphite coating. For the growth of CNTs, a thin layer (~4 nm) of nickel catalyst film was first deposited on graphite via e-beam deposition. Carbon nanotubes were subsequently grown on the surface of 3D graphite foam in C2H4 feedstock at 700 °C (Fig. 1c). It has been reported that there is a strong competition between carbon deposition and carbon removal during

TE D

the CNT growth on graphene layers using C2H4 feedstock at 800 °C [48-50]. Nevertheless, since the growth temperature was lower (700 °C), and the CNTs were grown on a thicker graphite foam in our

EP

study, no significant etching of the graphite foam was expected. We found that the annealing of nickel catalyst film on graphite foam played a significant role to the assembly of the subsequently grown

AC C

CNTs. Without the annealing of nickel catalyst, carbon nanotubes would grow into bundle state (i), while the annealing of nickel catalysts would result in the growth of carbon nanotubes in well-dispersed state (ii).

7

SC

RI PT

ACCEPTED MANUSCRIPT

M AN U

Fig. 1 Schematic illustration of controlled carbon nanotube growth on graphite foam. (a) Nickel nanofoam was used as 3D templates to grow graphite. Then nickel was etched in hydrochloric acid. (b) A thin layer of nickel was deposited as catalyst and carbon nanotubes were subsequently grown on the surface of 3D graphite foam. (c) The assembly of carbon nanotubes can be controlled by the annealing

CNTs on graphite foam.

TE D

process: (i) no annealing: bundled-state CNTs on graphite foam; (ii) with annealing: well-dispersed-state

EP

3.2 Characterizations of the superstructures

The SEM images of the carbon nanotubes on top of the graphite foam with and without

AC C

annealing of the Ni catalysts were showed in Fig. 2a and 2c, respectively. The annealing of the Ni/graphite foam performed at 700 °C for 30 min caused dewetting of the Ni catalysts film, forming nickel nanoislands with higher density and smaller diameter variation on the graphite foam [51]. The formation of dispersed catalytic nanoislands promoted the growth of the dispersed CNTs on the graphite foam (Fig. 2b). The obtained CNTs have diameters of less than 40 nm and wall thicknesses of ~5 nm on the graphite foam (inset of Fig. 2b). In contrast, bundled CNTs (Fig. 2d) were obtained without the annealing process. Higher magnification SEM images were provided in Fig. S1(e,f) to further present

8

ACCEPTED MANUSCRIPT

the 3D superstructures under different length scales. The BET surface area of well-dispersed CNTs on graphite foam was measured to be 31.49 m2/g, which is almost 2 times of the surface area of bundledCNTs on graphite foam at 19.35 m2/g (Fig. S2). The difference in surface area came from the highly

RI PT

dispersed state of the CNTs compared to their bundled assemblies. The BET surface areas of both CNT assemblies on graphite foams were larger compared with previous reports on other inorganic/graphite nanofoam structures [52, 53]. We used Raman spectroscopy and X-ray diffraction to identify the

SC

structure of the well-dispersed CNTs on graphite foam. The Raman spectrum of the graphite foam presented three typical peaks, D, G, and weak G’ peaks at 1348, 1582 and 2702 cm-1, respectively (Fig.

M AN U

2e). After the growth of CNTs, the Raman spectrum of the well-dispersed CNTs on graphite foam exhibited similar Raman features located at 1345, 1586 and 2697 cm-1, respectively. The G and G’ peaks indicated the ideal graphitic sp2 materials, while D peak represented the disordered graphitic lattice [54]. These features were similar to those seen for the multiwalled CNTs [55] and CNT/graphene hybrid

TE D

superstructures [51], confirming the structural quality of the CNTs/graphite foam. While no significant peak shifts are observed, the intensity ratio of D/G peaks was increased, in the case of CNTs on graphite foam. The increased in the intensity ratio of D/G peaks indicated an increased number of defects in the

EP

superstructure, which was typical for growth of CNTs at low temperature. The low-crystalline CNTs had been reported to be beneficial for the lithiation/delithiation process [47, 56]. The XRD pattern (Fig. 2f)

AC C

of both graphite foam and well-dispersed CNTs on graphite foam displayed a sharp and high intensity peak at the angle (2θ) of 25.5°, corresponding to the (002) plane of the hexagonal graphite structure of the multiwalled CNTs [57], further confirming the high crystallinity of the CNTs/graphite foam.

9

SC

RI PT

ACCEPTED MANUSCRIPT

Fig. 2 Low- and high-resolution scanning electron microscope (SEM) images of the well-dispersed (a

M AN U

and b) and bundled (c and d) CNTs grown on the graphite foam, respectively. The inset in (b) was a transmission electron microscope (TEM) image of the well-dispersed CNTs. Raman spectrum (e) and Xray diffraction (XRD) (f) of graphite foam and well-dispersed CNTs on graphite foam were measured to

TE D

characterize the structural quality of these superstructures.

3.3 Electrochemical performance of the materials The performance of well-dispersed CNTs on graphite (G-CNT) superstructures were found to be

EP

higher than that of bundled CNTs on graphite (G-BCNT) superstructures, as shown in Fig. 3a. Such superior specific capacity was more apparent at higher cycling rate. At high charging and discharging

AC C

current densities above 500



, G-CNT superstructures can still maintain high specific capacity.

We attributed this improvement to that the dispersed assembly provided larger surface area resulting in more reaction sites for Li intercalations/deintercalations [58-60]. The Coulombic efficiency for both samples were greater than 95%. Such high electrochemical performance was able to be retained when cycled at 100



after high speed cycling. A cyclic voltammetry (CV) profile with a voltage range

of 0-2 V was shown in Fig. 3b. G-CNT superstructures revealed a cathodic response with a peak at

10

ACCEPTED MANUSCRIPT

around 0.2 V, which could be attributed to the formation of solid electrolyte interface (SEI) and lithiumcarbon intercalation product LiC6 [22, 61-63]. This characteristic behavior was maintained after 10 cycles, suggesting high reversibility. The galvanostatic charge/discharge diagram of G-CNT

RI PT

superstructures with a voltage range of 0-3 V at different current densities was presented in Fig. 3c. A plateau at around 0.1 V was observed at both cycling rates during discharging. The G-CNTs had a



after 100 cycles with a rate of 500

ℎ

at 100



and still retained above 200

ℎ

. Such performance and retention were much better compared

SC

superior specific capacity of above 500

with the graphite foam and G-BCNT superstructures (see Fig. S3 for details). Raji et al. had

M AN U

demonstrated that during cycling lithium was able to be plated homogeneously throughout graphene and CNT bundle surfaces with their ultra-high surface area, and thus leading to improved electrochemical performance as lithium ion battery anode materials [58]. The specific capacities and Coulombic

efficiencies of graphite foam, G-CNT and G-BCNT superstructures at cycling rate of 500



ℎ

. The rate at the 1st cycle was 100

TE D

compared in Fig. 3d, compared with commercial G at 200

were

due to the need of anode materials activation in order to to obtain a stable SEI formation [33].

Over 120 cycles, G-CNT superstructures overall exhibited higher capacity above 215

ℎ

with

EP

greater than 95% Columbic efficiency (CE) after the first cycle while the first cycle Columbic efficiency for them were both 90%. The subtracted specific capacity of CNTs and B-CNTs only without

AC C

considering the graphite foam were calculated and shown in Fig. 3e. As expected, CNTs showed a specific capacity of above 516

ℎ

, compared with over 381

ℎ

from BCNTs. The specific

capacity increased gradually and stabilized after 110th cycle (Fig. S4) to above 800 CNT electrode compared with the BCNTs at around 500

ℎ

ℎ

of the

.We speculate such capacity rise

ascribing to the gradual activation of CNTs due to increased active sites. During cycling, the volume change induced by insertion/extraction of Li ions would rearrange of CNTs, resulting more accessible

11

ACCEPTED MANUSCRIPT

sites in contact with electrolyte for intercalation [64, 65]. Similar behavior has been reported with other carbon nanostructures [66, 67]. Such superior performance was expected due to the nature of the G-CNT superstructures allowing high-rate charge transportation, high lithiation/delithiation surface area and

ℎ

RI PT

more stable SEI formation [68]. Hybrid structure of CNTs with graphene were reported with over 200 increase in capacity after CNTs addition [38, 46]. The free-standing electrodes also

demonstrated higher performance compared to a previous report with similar materials coated with at similar charge and discharge rate [33].

SC

ℎ

AC C

EP

TE D

M AN U

slurry with a specific capacity of around 500

12

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

Fig. 3 (a) Rate capability, cycling performance and Coulombic efficiency of well-dispersed CNTs on graphite and bundled CNTs on graphite foam electrodes. (b) Cyclic voltammetry characteristic of CNTs

13

ACCEPTED MANUSCRIPT

on graphite foam. (c) Galvanostatic charge-discharge profiles of CNTs on graphite foam. (d) Cycling performance and Coulombic efficiency of electrodes made by graphite foam, CNTs on graphite foam

M AN U

SC

foam, CNTs only and CNT bundles electrodes.

RI PT

and CNT bundles on graphite foam. (e) Cycling performance and Coulombic efficiency of graphite

Fig. 4 Nyquist plots of (a) graphite, (b) bundled CNTs on graphite foam and (c) dispersed CNTs on

TE D

graphite foam over 10 charge/discharge cycles.

In order to better understand the interfacial kinetics of our LIBs within its closed system,

EP

electrochemical impedance spectroscopy (EIS) was performed. The Nyquist plots of LIB cells with anode electrodes of graphite, G-BCNT and G-CNT superstructures for the 1st, 3rd, 6th, 8th and 10th cycles

AC C

were shown in Fig. 4a-c, respectively. The EIS experiments were carried out using the equivalent circuit shown in Fig. S5, according to previous methods [35]. Each data point of the Nyquist plots represented the impedance behavior in a specific frequency that decreased along the horizontal axis. For all electrodes, the high frequency (HF) region contained two depressed semicircles. The first one was associated with SEI formation, while the other one was related to the contact impedance between the electrode current collector with active materials/conductivity enhancing additives and binder matrix [6971]. One semicircle in the middle frequency region was associated with charge transfer resistance (Rct).

14

ACCEPTED MANUSCRIPT

In addition, a sloped line related to Warburg impedance caused by Li-ion diffusion into the electrode material matrix in low frequency region were also presented in Nyquist plots. The equivalent series resistance (ESR or Rs) in the equivalent circuit for EIS fitting represented the electrode impedance

RI PT

related to the electrolyte, electrodes and current collectors. We observed resistance decrease for all samples. We believe such behavior could be ascribed to the activation of electrode materials with improved wettability between electrode and electrolyte [72]. Moreover, after intercalation, the spacing

SC

between graphite layers was enlarged that could facilitate Li ion insertion/extraction, leading to lowered resistance [73]. The ESR values of the three electrodes in Fig. 5a showed similar behaviors over the first

M AN U

10 cycles with stable curves that are gradually declining. As expected, dispersed CNTs superstructures had the lowest ESR values at all cycles. Fig. 5b showed the SEI and interphase contact resistance (RSEI+int) for the first 10 cycles for all three electrodes after fitting. For graphite foam and G-BCNT superstructures, the RSEI+int dropped during the first 5 cycles, indicating continuous SEI formation, while

TE D

the G-CNTs superstructure based electrode had no noticeable fluctuation over the cycle range, indicating very stable SEI. The G-CNT superstructure based electrode also yielded the lowest charge transfer resistance among all in Fig. S6. This could be attributed to its high surface area with seamless

AC C

matrix.

EP

connection to graphite foam resulting in higher and more efficient charge transfer within the electrode

15

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

EP

Fig. 5 Comparisons of (a) equivalent series resistance (ESR) and (b) SEI and interphase electronic contact resistance over 10 cycles between graphite, bundled CNTs on graphite foam, and dispersed

AC C

CNTs on graphite foam.

16

ACCEPTED MANUSCRIPT

4. Conclusion To summarize, free-standing hybrid 3D superstructures of carbon nanotubes on graphite foam had been utilized as LIB anodes materials without the need of additional additives and current

RI PT

collectors. Furthermore, we were able to obtain carbon nanotubes with two distinct assemblies (welldispersed CNTs vs. bundled CNT) by controlling the geometry of nickel catalyst prior to CNT growth. With controlled growth conditions, we were able to obtain dispersed CNTs with a specific capacity of , higher than that of the bundled CNTs. This performance was nearly four times

SC

ℎ

over 800

more than commercial graphite anodes. Besides seeking future-generation electrode materials,

M AN U

improving performance of current anode materials can provide instant values to the battery industry. The investigation of carbon nanotube assemblies provides new insights in optimizing carbon materialbased LIB anodes.

TE D

Acknowledgements

Financial support from the Office of Research at the University of California, Riverside is gratefully acknowledged. This work was made use of the Center for Nanoscale Science and Engineering (CNSE)

EP

at UCR. The electron microscopy was performed in the Center Facility for Advanced Microscopy and

AC C

Microanalysis (CFAMM) at UCR.

Appendix

Supplementary data related to this article are available at: XXX

17

ACCEPTED MANUSCRIPT

References [1] M. Armand, J.M. Tarascon, Building better batteries, Nature 451(7179) (2008) 652-657. [2] Y. Yang, G. Zheng, Y. Cui, Nanostructured sulfur cathodes, Chemical Society Reviews 42(7) (2013) 3018-3032. [3] C. de las Casas, W. Li, A review of application of carbon nanotubes for lithium ion battery anode material, Journal of

RI PT

Power Sources 208 (2012) 74-85.

[4] V. Etacheri, R. Marom, R. Elazari, G. Salitra, D. Aurbach, Challenges in the development of advanced Li-ion batteries: a review, Energy & Environmental Science 4(9) (2011) 3243-3262.

[5] F. Cheng, J. Liang, Z. Tao, J. Chen, Functional Materials for Rechargeable Batteries, Advanced Materials 23 (2011) 1695-715.

SC

[6] X. Fan, L. Chen, X. Ji, T. Deng, S. Hou, J. Chen, J. Zheng, F. Wang, J. Jiang, K. Xu, C. Wang, Highly Fluorinated Interphases Enable High-Voltage Li-Metal Batteries, Chem 4(1) (2018) 174-185.

[7] C. Li, C. Liu, W. Wang, Z. Mutlu, J. Bell, K. Ahmed, R. Ye, M. Ozkan, C.S. Ozkan, Silicon Derived from Glass Bottles

M AN U

as Anode Materials for Lithium Ion Full Cell Batteries, Scientific Reports 7(1) (2017) 917.

[8] W. Wang, Z. Favors, C. Li, C. Liu, R. Ye, C. Fu, K. Bozhilov, J. Guo, M. Ozkan, C.S. Ozkan, Silicon and Carbon Nanocomposite Spheres with Enhanced Electrochemical Performance for Full Cell Lithium Ion Batteries, Scientific Reports 7 (2017) 44838.

[9] C. Gao, N.D. Kim, R. Villegas Salvatierra, S.-K. Lee, L. Li, Y. Li, J. Sha, G.A.L. Silva, H. Fei, E. Xie, J.M. Tour, Germanium on seamless graphene carbon nanotube hybrids for lithium ion anodes, Carbon 123 (2017) 433-439. [10] A.C. Serino, J.S. Ko, M.T. Yeung, J.J. Schwartz, C.B. Kang, S.H. Tolbert, R.B. Kaner, B.S. Dunn, P.S. Weiss, Lithium-

TE D

Ion Insertion Properties of Solution-Exfoliated Germanane, ACS Nano 11(8) (2017) 7995-8001. [11] Y.J. Hong, Y.C. Kang, One-pot synthesis of core–shell-structured tin oxide–carbon composite powders by spray pyrolysis for use as anode materials in Li-ion batteries, Carbon 88 (2015) 262-269. [12] H.S. Ju, Y.J. Hong, J.S. Cho, Y.C. Kang, Strategy for yolk-shell structured metal oxide-carbon composite powders and their electrochemical properties for lithium-ion batteries, Carbon 100 (2016) 137-144.

EP

[13] F. Cheng, J. Chen, Something from nothing, Nature Chemistry 4 (2012) 962. [14] F. Cheng, J. Chen, Metal-air batteries: from oxygen reduction electrochemistry to cathode catalysts, Chemical Society

AC C

Reviews 41(6) (2012) 2172-2192.

[15] Y. Hu, T. Zhang, F. Cheng, Q. Zhao, X. Han, J. Chen, Recycling Application of Li–MnO2 Batteries as Rechargeable Lithium–Air Batteries, Angewandte Chemie International Edition 54(14) (2015) 4338-4343. [16] X. Yang, L. Zhang, F. Zhang, Y. Huang, Y. Chen, Sulfur-Infiltrated Graphene-Based Layered Porous Carbon Cathodes for High-Performance Lithium–Sulfur Batteries, ACS Nano 8(5) (2014) 5208-5215. [17] M. Zhang, Z. Sun, T. Zhang, D. Sui, Y. Ma, Y. Chen, Excellent cycling stability with high SnO2 loading on a threedimensional graphene network for lithium ion batteries, Carbon 102 (2016) 32-38. [18] F. Zhang, X. Yang, Y. Xie, N. Yi, Y. Huang, Y. Chen, Pyrolytic carbon-coated Si nanoparticles on elastic graphene framework as anode materials for high-performance lithium-ion batteries, Carbon 82 (2015) 161-167. [19] L. Noerochim, J.-Z. Wang, S.-L. Chou, D. Wexler, H.-K. Liu, Free-standing single-walled carbon nanotube/SnO2 anode paper for flexible lithium-ion batteries, Carbon 50(3) (2012) 1289-1297.

18

ACCEPTED MANUSCRIPT

[20] N. Zhang, F. Cheng, Y. Liu, Q. Zhao, K. Lei, C. Chen, X. Liu, J. Chen, Cation-Deficient Spinel ZnMn2O4 Cathode in Zn(CF3SO3)2 Electrolyte for Rechargeable Aqueous Zn-Ion Battery, Journal of the American Chemical Society 138(39) (2016) 12894-12901. [21] Y. Zhu, Y. Wen, X. Fan, T. Gao, F. Han, C. Luo, S.-C. Liou, C. Wang, Red Phosphorus–Single-Walled Carbon Nanotube Composite as a Superior Anode for Sodium Ion Batteries, ACS Nano 9(3) (2015) 3254-3264.

RI PT

[22] B. Campbell, R. Ionescu, Z. Favors, C.S. Ozkan, M. Ozkan, Bio-Derived, Binderless, Hierarchically Porous Carbon Anodes for Li-ion Batteries, Scientific Reports 5 (2015) 14575.

[23] S. Flandrois, B. Simon, Carbon materials for lithium-ion rechargeable batteries, Carbon 37(2) (1999) 165-180. [24] Z. Pan, H. Sun, J. Pan, J. Zhang, B. Wang, H. Peng, The creation of hollow walls in carbon nanotubes for highperformance lithium ion batteries, Carbon 133 (2018) 384-389.

SC

[25] Y. Zhang, Y. Jiao, M. Liao, B. Wang, H. Peng, Carbon nanomaterials for flexible lithium ion batteries, Carbon 124 (2017) 79-88.

[26] L.G. Bulusheva, A.V. Okotrub, A.G. Kurenya, H. Zhang, H. Zhang, X. Chen, H. Song, Electrochemical properties of

M AN U

nitrogen-doped carbon nanotube anode in Li-ion batteries, Carbon 49(12) (2011) 4013-4023.

[27] Y. Yang, S. Jin, Z. Zhang, Z. Du, H. Liu, J. Yang, H. Xu, H. Ji, Nitrogen-Doped Hollow Carbon Nanospheres for HighPerformance Li-Ion Batteries, ACS Applied Materials & Interfaces 9(16) (2017) 14180-14186. [28] Z. Du, J. Xu, S. Jin, Y. Shi, C. Guo, X. Kong, Y. Zhu, H. Ji, The correlation between carbon structures and electrochemical properties of sulfur/carbon composites for Li-S batteries, Journal of Power Sources 341 (2017) 139-146. [29] W. Li, X. Xu, C. Liu, M.C. Tekell, J. Ning, J. Guo, J. Zhang, D. Fan, Ultralight and Binder-Free All-Solid-State Flexible Supercapacitors for Powering Wearable Strain Sensors, Advanced Functional Materials 27(39) (2017) 1702738.

TE D

[30] L. Sun, X. Wang, Y. Wang, Q. Zhang, Roles of carbon nanotubes in novel energy storage devices, Carbon 122 (2017) 462-474.

[31] Z. Zhu, S. Wang, J. Du, Q. Jin, T. Zhang, F. Cheng, J. Chen, Ultrasmall Sn Nanoparticles Embedded in Nitrogen-Doped Porous Carbon As High-Performance Anode for Lithium-Ion Batteries, Nano Letters 14(1) (2014) 153-157.

40(10) (2002) 1775-1787.

EP

[32] E. Frackowiak, F. Béguin, Electrochemical storage of energy in carbon nanotubes and nanostructured carbons, Carbon

[33] W. Wang, I. Ruiz, S. Guo, Z. Favors, H.H. Bay, M. Ozkan, C.S. Ozkan, Hybrid carbon nanotube and graphene

AC C

nanostructures for lithium ion battery anodes, Nano Energy 3 (2014) 113-118. [34] F.-S. Ke, Y.-S. Wu, H. Deng, Metal-organic frameworks for lithium ion batteries and supercapacitors, Journal of Solid State Chemistry 223 (2015) 109-121.

[35] C. Li, C. Liu, K. Ahmed, Z. Mutlu, Y. Yan, I. Lee, M. Ozkan, C.S. Ozkan, Kinetics and electrochemical evolution of binary silicon-polymer systems for lithium ion batteries, RSC Advances 7(58) (2017) 36541-36549. [36] H. Ji, L. Zhang, M.T. Pettes, H. Li, S. Chen, L. Shi, R. Piner, R.S. Ruoff, Ultrathin Graphite Foam: A ThreeDimensional Conductive Network for Battery Electrodes, Nano Letters 12(5) (2012) 2446-2451. [37] B.J. Landi, M.J. Ganter, C.D. Cress, R.A. DiLeo, R.P. Raffaelle, Carbon nanotubes for lithium ion batteries, Energy & Environmental Science 2(6) (2009) 638-654.

19

ACCEPTED MANUSCRIPT

[38] E. Yoo, J. Kim, E. Hosono, H.-s. Zhou, T. Kudo, I. Honma, Large Reversible Li Storage of Graphene Nanosheet Families for Use in Rechargeable Lithium Ion Batteries, Nano Letters 8(8) (2008) 2277-2282. [39] W. Wang, S. Guo, M. Penchev, I. Ruiz, K.N. Bozhilov, D. Yan, M. Ozkan, C.S. Ozkan, Three dimensional few layer graphene and carbon nanotube foam architectures for high fidelity supercapacitors, Nano Energy 2(2) (2013) 294-303. [40] M. Down, C.E. Banks, Freestanding three-dimensional Graphene Macroporous Supercapacitor, ACS Applied Energy

RI PT

Materials 1(2) (2018) 891-899.

[41] X. Fan, J. Shao, X. Xiao, L. Chen, X. Wang, S. Li, H. Ge, Carbon encapsulated 3D hierarchical Fe3O4 spheres as advanced anode materials with long cycle lifetimes for lithium-ion batteries, Journal of Materials Chemistry A 2(35) (2014) 14641-14648.

[42] V. Jourdain, C. Bichara, Current understanding of the growth of carbon nanotubes in catalytic chemical vapour

SC

deposition, Carbon 58 (2013) 2-39.

[43] B. Gao, C. Bower, J.D. Lorentzen, L. Fleming, A. Kleinhammes, X.P. Tang, L.E. McNeil, Y. Wu, O. Zhou, Enhanced saturation lithium composition in ball-milled single-walled carbon nanotubes, Chemical Physics Letters 327(1) (2000) 69-75.

M AN U

[44] G. Li, L. Xu, Q. Hao, M. Wang, Y. Qian, Synthesis, characterization and application of carbon nanocages as anode materials for high-performance lithium-ion batteries, RSC Advances 2(1) (2012) 284-291. [45] C. Liu, F. Li, L.-P. Ma, H.-M. Cheng, Advanced Materials for Energy Storage, Advanced Materials 22(8) (2010) E28E62.

[46] B.P. Vinayan, R. Nagar, V. Raman, N. Rajalakshmi, K.S. Dhathathreyan, S. Ramaprabhu, Synthesis of graphenemultiwalled carbon nanotubes hybrid nanostructure by strengthened electrostatic interaction and its lithium ion battery application, Journal of Materials Chemistry 22(19) (2012) 9949-9956.

TE D

[47] Z. Yan, L. Ma, Y. Zhu, I. Lahiri, M.G. Hahm, Z. Liu, S. Yang, C. Xiang, W. Lu, Z. Peng, Z. Sun, C. Kittrell, J. Lou, W. Choi, P.M. Ajayan, J.M. Tour, Three-Dimensional Metal–Graphene–Nanotube Multifunctional Hybrid Materials, ACS Nano 7(1) (2013) 58-64.

[48] D.P. Hunley, S.L. Johnson, J.K. Stieha, A. Sundararajan, A.T. Meacham, I.N. Ivanov, D.R. Strachan,

EP

Crystallographically Aligned Carbon Nanotubes Grown on Few-Layer Graphene Films, ACS Nano 5(8) (2011) 6403-6409. [49] L.C. Campos, V.R. Manfrinato, J.D. Sanchez-Yamagishi, J. Kong, P. Jarillo-Herrero, Anisotropic Etching and Nanoribbon Formation in Single-Layer Graphene, Nano Letters 9(7) (2009) 2600-2604.

2689.

AC C

[50] L.P. Biró, P. Lambin, Nanopatterning of graphene with crystallographic orientation control, Carbon 48(10) (2010) 2677-

[51] K. Kumar, Y.-S. Kim, X. Li, J. Ding, F.T. Fisher, E.-H. Yang, Chemical Vapor Deposition of Carbon Nanotubes on Monolayer Graphene Substrates: Reduced Etching via Suppressed Catalytic Hydrogenation Using C2H4, Chemistry of Materials 25(19) (2013) 3874-3879.

[52] J. Ning, X. Xu, C. Liu, D.L. Fan, Three-dimensional multilevel porous thin graphite nanosuperstructures for Ni(OH)2based energy storage devices, Journal of Materials Chemistry A 2(38) (2014) 15768-15773. [53] C. Li, C. Liu, W. Wang, J. Bell, Z. Mutlu, K. Ahmed, R. Ye, M. Ozkan, C.S. Ozkan, Towards flexible binderless anodes: silicon/carbon fabrics via double-nozzle electrospinning, Chemical Communications 52(76) (2016) 11398-11401.

20

ACCEPTED MANUSCRIPT

[54] M.S. Dresselhaus, A. Jorio, M. Hofmann, G. Dresselhaus, R. Saito, Perspectives on Carbon Nanotubes and Graphene Raman Spectroscopy, Nano Letters 10(3) (2010) 751-758. [55] C. Jia-jia, J. Xin, S. Qiu-jie, W. Chong, Z. Qian, Z. Ming-sen, D. Quan-feng, The preparation of nano-sulfur/MWCNTs and its electrochemical performance, Electrochimica Acta 55(27) (2010) 8062-8066.

Batteries, Journal of Carbon Research 2(4) (2016) 23.

RI PT

[56] C. Kang, E. Cha, M. Patel, H. Wu, W. Choi, Three-Dimensional Carbon Nanostructures for Advanced Lithium-Ion

[57] A. Cao, C. Xu, J. Liang, D. Wu, B. Wei, X-ray diffraction characterization on the alignment degree of carbon nanotubes, Chemical Physics Letters 344(1) (2001) 13-17.

[58] A.-R.O. Raji, R. Villegas Salvatierra, N.D. Kim, X. Fan, Y. Li, G.A.L. Silva, J. Sha, J.M. Tour, Lithium Batteries with Nearly Maximum Metal Storage, ACS Nano 11(6) (2017) 6362-6369.

SC

[59] Z. Liang, D. Lin, J. Zhao, Z. Lu, Y. Liu, C. Liu, Y. Lu, H. Wang, K. Yan, X. Tao, Y. Cui, Composite lithium metal anode by melt infusion of lithium into a 3D conducting scaffold with lithiophilic coating, Proceedings of the National Academy of Sciences 113(11) (2016) 2862-2867.

M AN U

[60] C.-P. Yang, Y.-X. Yin, S.-F. Zhang, N.-W. Li, Y.-G. Guo, Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes, Nature Communications 6 (2015) 8058. [61] T. Zheng, J.R. Dahn, The effect of turbostratic disorder on the staging transitions in lithium intercalated graphite, Synthetic Metals 73(1) (1995) 1-7.

[62] R. Paul, V. Etacheri, V.G. Pol, J. Hu, T.S. Fisher, Highly porous three-dimensional carbon nanotube foam as a freestanding anode for a lithium-ion battery, RSC Advances 6(83) (2016) 79734-79744. [63] A.P. Cohn, L. Oakes, R. Carter, S. Chatterjee, A.S. Westover, K. Share, C.L. Pint, Assessing the improved performance

TE D

of freestanding, flexible graphene and carbon nanotube hybrid foams for lithium ion battery anodes, Nanoscale 6(9) (2014) 4669-4675.

[64] M. Chen, J. Liu, D. Chao, J. Wang, J. Yin, J. Lin, H. Jin Fan, Z. Xiang Shen, Porous α-Fe2O3 nanorods supported on carbon nanotubes-graphene foam as superior anode for lithium ion batteries, Nano Energy 9 (2014) 364-372.

1138.

EP

[65] Z. Xiong, Y. Yun, H.-J. Jin, Applications of Carbon Nanotubes for Lithium Ion Battery Anodes, Materials 6(3) (2013)

[66] C. Kang, I. Lahiri, R. Baskaran, W.-G. Kim, Y.-K. Sun, W. Choi, 3-dimensional carbon nanotube for Li-ion battery

AC C

anode, Journal of Power Sources 219 (2012) 364-370. [67] C. Chen, R. Agrawal, Y. Hao, C. Wang, Activated Carbon Nanofibers as High Capacity Anodes for Lithium-Ion Batteries, ECS Journal of Solid State Science and Technology 2(10) (2013) M3074-M3077. [68] Z. Chen, W. Ren, L. Gao, B. Liu, S. Pei, H.-M. Cheng, Three-dimensional flexible and conductive interconnected graphene networks grown by chemical vapour deposition, Nature Materials 10(6) (2011) 424-428. [69] J. Guo, A. Sun, X. Chen, C. Wang, A. Manivannan, Cyclability study of silicon–carbon composite anodes for lithiumion batteries using electrochemical impedance spectroscopy, Electrochimica Acta 56(11) (2011) 3981-3987. [70] J. Guo, X. Chen, C. Wang, Carbon scaffold structured silicon anodes for lithium-ion batteries, Journal of Materials Chemistry 20(24) (2010) 5035-5040.

21

ACCEPTED MANUSCRIPT

[71] M. Gaberscek, J. Moskon, B. Erjavec, R. Dominko, J. Jamnik, The Importance of Interphase Contacts in Li Ion Electrodes: The Meaning of the High-Frequency Impedance Arc, Electrochemical and Solid-State Letters 11(10) (2008) A170-A174. [72] Z. Lei, Q. Yang, Y. Xu, S. Guo, W. Sun, H. Liu, L.-P. Lv, Y. Zhang, Y. Wang, Boosting lithium storage in covalent organic framework via activation of 14-electron redox chemistry, Nature Communications 9(1) (2018) 576.

RI PT

[73] T.-H. Kim, E.K. Jeon, Y. Ko, B.Y. Jang, B.-S. Kim, H.-K. Song, Enlarging the d-spacing of graphite and polarizing its

AC C

EP

TE D

M AN U

SC

surface charge for driving lithium ions fast, Journal of Materials Chemistry A 2(20) (2014) 7600-7605.

22