Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation

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Rapid polymerization synthesizing highcrystalline g-C3N4 towards boosting solar photocatalytic H2 generation Longyan Wang a, Yuanzhi Hong a,*, Enli Liu a,b, Zhiguo Wang a, Jiahui Chen a, Shuang Yang a, Jingbo Wang a, Xue Lin a,**, Junyou Shi a,b,*** a

School of Materials Science and Engineering, Beihua University, 3999 Binjiang East Road, Jilin, 132013, People's Republic of China b School of Agriculture and Food Engineering, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China

highlights

graphical abstract


The GCN-HC was firstly prepared by a one-step rapid polymerization strategy.
The GCN-HC shows an enhanced photocatalytic

activity

for

H2

evolution.
The GCN-HC presents the fast charge

transfer

efficiency

as

compared with GCN-B.
The GCN-HC can be as a promising photocatalyst

for

solar-to-H2

conversion.

article info

abstract

Article history:

Graphitic carbon nitride (g-C3N4) is a promising metal-free photocatalyst for solar photo-

Received 2 November 2019

catalytic hydrogen gas (H2) generation from water. In particularly, high-crystalline g-C3N4

Received in revised form

(GCN-HC) material with fewer structural defects possesses the fast photoexcited electron-

15 December 2019

hole pair's separation efficiency as comparison with bulk g-C3N4 (GCN-B) powders, leading

Accepted 23 December 2019

to the drastic improvement of photocatalytic activity. However, the fabrication of such

Available online xxx

GCN-HC photocatalyst by a simple and economical synthesis approach still remains a challenge. Herein, we firstly develop a one-step rapid polymerization strategy for synthe-

Keywords:

sizing the GCN-HC, that is direct calcination of melamine at 550  C not only without the

High-crystalline g-C3N4

early heating process, but also without the assistance of any additive or salt intercalation.

* Corresponding author. ** Corresponding author. *** Corresponding author. School of Materials Science and Engineering, Beihua University, 3999 Binjiang East Road, Jilin, 132013, People's Republic of China. E-mail addresses: [email protected] (Y. Hong), [email protected] (X. Lin), [email protected] (J. Shi). https://doi.org/10.1016/j.ijhydene.2019.12.168 0360-3199/© 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Rapid polymerization

As a result, the GCN-HC exhibits an obviously boosting visible-light-induced photocatalytic

One-step synthesis

H2-generation performance, which is over 2.06-folds much greater than that of GCN-B. Our

Photocatalysis

work provides an available one-step synthetic strategy for the large-scale preparation of

H2 generation

high performance GCN-HC towards sustainable solar-to-chemical energy conversion.

Solar energy conversion

© 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Introduction In recent years, the emerging green and clean renewable energy sources are becoming a hot topic in addressing global energy crisis and environment issues. Especially, utilizing and converting sustainable solar energy into chemical fuels, such as the photocatalytic hydrogen gas (H2) generation from water has been considered as a promising technology [1e3]. However, the traditional semiconductors (TiO2, CdS, SrTiO3, etc.) for photocatalytic H2 production reaction have some disadvantages. For example, the most commonly used TiO2 photocatalyst can only absorb a small amount of ultraviolet light in sunlight because of its large band gap [4]. Meanwhile, the unstable CdS would produce the toxic Cd2þ heavy metal under visible light, which is greatly limited photocatalysis applications [5]. Additionally, the synthetic processes of various nanomaterials are more complex for its industrial deployment [6]. Thus, the focus of research in photocatalysis is to develop high-efficiency photocatalyst with visible-lightdriven response, environmental friendliness, and stability. Recently, graphitic carbon nitride (g-C3N4) has attracted more and more attention in the photocatalytic applications [7e12], since Wang and his co-workers firstly discovered it could produce H2 from water in 2009 [13]. g-C3N4 (GCN) is a promising metal-free abundance photocatalyst with lots of unique features, such as good physical-chemical stability, reasonable cost, and tunable electronic structure [14,15]. Generally, bulk GCN (GCN-B) can be directly prepared by the thermal polycondensation of the inexpensive nitrogencontaining precursors. Nevertheless, the GCN-B only shows poor photocatalytic efficiency, which is mainly attributed to the severe charge recombination [16e18]. To overcome the drawbacks and improve photoreactivity of GCN-B, many efficient approaches have been developed, such as exfoliation into 2D nanosheets [11,19e21], co-catalysts loading [22e24], structures optimization [25e27], heterostructures construction [10,18,28e30], elements doping [31e33], and etc. At present, the scientists have been largely focus on the high-crystalline g-C3N4 (GCN-HC) towards photocatalytic water splitting [34e40]. The intrinsic properties of GCN-HC with fewer structural defects would effectively accelerate the separation and transfer of charge carries, resulting in the greatly enhancement of photoactivity [41,42]. Unfortunately, lots of the synthetic paths of such GCN-HC materials are complicated, multi-steps and time-consuming. For example, the ionothermal method involved in molten salts is the most popular route to prepare high-efficiency GCN-HC, yet it must introduce LiCl/KCl as the high-temperature solvent [34e37,39,40]. Although the microwave-assisted route is a

faster and robust approach to fabricate GCN-HC with improved performance, it must require for the high microwave power [43e45]. Moreover, others successful strategies such as liquid exfoliation [46], protonation-activated polycondensation [47], Ni-foam as template [48], and introducing hollow silica spheres were emerged [49], yet those methodologies are still difficult for it practical synthesis. Clearly, a simple one-step synthetic strategy for the scale up fabrication of GCN-HC in an electric furnace is desirable but challenging. It is documented that GCN-B powders derived from the thermal polymerization reaction could decompose into two processes: (i) produced melem units via heating the precursors from room temperature to high temperature; (ii) formed melon structure by condensation of melem at around 550  C [9,50]. In order to short the reaction time for its practical preparation, here a one-step rapid polymerization strategy is developed to fabricate the GCN-HC photocatalyst for the first time via the direct calcination of melamine at 550  C, which not only without the early heating process, but also without the assistance of any additive or salt intercalation. The photocatalytic activity of as-obtained catalysts were studied by photoreduction of water under visible light irradiation (l > 420 nm). Subsequently, the physic-chemical properties of the products were characterized via multiple techniques. Compared to GCN-B, the GCN-HC has higher crystalline structure, faster photoinduced charge transfer efficiency and larger Hþ thermodynamic driving force. Result suggests that the as-fabricated GCN-HC exhibits an enhanced photocatalytic H2-generation performance (339.4 mmol g1 h1), which is 2.06-folds higher than that of GCN-B powders under the same condition. Our work offers a simple one-step and new rap polymerization strategy to directly prepare the highly crystalline GCN photocatalyst for solar-to-fuel conversion.

Experimental section Synthesis of GCN-HC and GCN-B Melamine is analytical grade and used as received. For synthesizing GCN-B, 5 g of melamine were placed into a 50 mL covered alumina crucible, then calcined from 25  C  to 550  C with a heating rate of 2.3 C/min. With further thermal polymerization reaction for 4 h at 550  C, the GCN-B powders were obtained through grinding after cooling to the room temperature. For synthesizing GCNHC, the one-step rapid polymerization strategy is different from the commonly thermal polymerization route, that is only direct calcination of melamine at 550  C

Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Characterization

Fig. 1 e Experimental processes diagram for the preparation of GCN-B and GCN-HC.

for reaction 4 h without the early heating process or assistance of any additive. The schematic processes for the synthesis of GCN-B and GCN-HC were illustrated in Fig. 1.

The morphologies of as-prepared photocatalysts were observed by a scanning electron microscopy (SEM, JSM6700F, Japan). The microstructures and thickness of asfabricated photocatalysts were carried out by the transmission electron microscopy (TEM, Tecnai G2 F20, American) and atomic force microscopy (AFM, Asylum Research MFP930, America), respectively. Raman spectra were measured on an inVia Raman Microscope (Renishaw Instruments) equipped with a diode laser of excitation at 633 nm. The crystal structures of as-synthesized photocatalysts were determined by an X-ray diffraction (XRD, X'Pert-Pro MPD, Holland). Electron paramagnetic resonance (EPR) spectra were collected by an EPR A 320 (Bruker Instrument, Germany) spectrometer. The functional groups of as-obtained photocatalysts were characterized by a Fourier transform infrared spectrometer (FT-IR, Nexus 470, American). The X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption isotherms were performed on the Thermo ESCALAB 250XI (America) and TriStar II 3020 (America), respectively. The optical properties of as-made photocatalysts were recorded by an UVevis Lambda 365 spectrophotometer (America). The Mott-Schottky plots, electrochemical impedance spectroscopy (EIS) and photocurrent measurements tests were measured on the CHI-

Fig. 2 e (a) XRD patterns and (b) the enlarged spectra of as-prepared GCN-B and GCN-HC. (c) Room-temperature EPR spectra and (d) Raman spectra of as-synthesized GCN-B and GCN-HC. Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Fig. 3 e (a) Typical SEM images of as-synthesized (a) GCN-B and (b) GCN-HC. Typical TEM and HRTEM images of as-prepared (c, e) GCN-B and (d, f) GCN-HC.

760E and CHI-660E electrochemical workstations (Chenhua Instruments, China) with a standard three-electrode configuration, respectively. The photoluminescence (PL) and time-resolved PL spectra were tested on LS 55 (America) and FLS 1000 (U K) spectrophotometer, respectively.

Photocatalytic hydrogen evolution tests The photocatalytic water splitting experiments were implemented in a Lab-H2 photocatalytic system (CEL-SPH2N, China

Education Au-Light). A 300 W Xenon arc lamp equipped with a 420 nm UV cut-off filter was chosen as the visible-light source (l > 420 nm) in the system. Briefly, 50 mg of photocatalysts were well dispersed in 100 mL aqueous solution containing 10 vol% triethanolamine as scavenger, then a certain amount of H2PtCl6$6H2O aqueous solution was added for the in-situ formation of 3 wt% Pt as cocatalyst. Subsequently, the oxygen dissolved in the aqueous solution was removed by pumping vacuum and the temperature was maintained at 5  C under the whole testing. The above solution was constantly stirred

Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Fig. 4 e Typical AFM images of as-fabricated (a) GCN-B and (c) GCN-HC. The height curves determined along the red lines over the (b) GCN-B and (d) GCN-HC samples. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

to keep the uniformity of suspension in the photocatalytic reaction. Finally, the quantitative gas was collected at the given time intervals and analyzed to get the specific content of H2 by a gas chromatograph (GC-7920, China Education AuLight, N2 as a carrier gas).

Results and discussion The crystal structures of the photocatalysts were studied by XRD analyse. As displayed in Fig. 2a, both GCN-B and GCN-HC samples have two distinct diffraction peaks located at approximately 13.1 (100) and 27.4 (002), which can be indexed to the in-plane repeated units and the interlayer stacking reflection for GCN materials, respectively [7,13,33,34,50e52]. Compared to GCN-B, the (002) plane intensity of GCN-HC is more sharper, indicating the high crystalline structure of GCN-HC product [39,41,43,48]. More importantly, the (002) diffraction peak of GCN-HC slightly shifts to high angle (27.59 ) in comparison with GCN-B (27.36 ) (Fig. 2b), suggesting the significant decreasing the interlayer distance between the basic layer sheets of GCN-HC [21,53]. Fig. 2c displays the room-temperature EPR spectra of GCN-B and GCN-HC, which the Lorentzian lines at g ¼ 2.0036

originate from the unpaired electrons in the carbon atoms. It can be seen the EPR intensity of GCN-HC is slightly low than that of GCN-B, further indicating the high crystalline structure of GCN-HC [36,54]. Fig. 2d shows the Raman spectra of GCN-B and GCN-HC with a 633 nm laser. It is difficult to observation any peaks on the information about CeN bonds in GCN-B, which may be caused by the strong fluorescence interference of g-C3N4 materials [55]. On the contrary, the GCN-HC has two weaker peaks at approximately 709 and 1232 cm1, corresponding to the vibration modes of CN heterocycles [55e57]. The morphologies and microstructures of GCN-B and GCNHC were observed by SEM and TEM analyses. As shown in Fig. 2a and b, GCN-B shows typically large agglomerates, but GCN-HC exhibits the sheet like structures with a size of several micrometers. Moreover, TEM image of GCN-B also presents stacking counterparts (Fig. 3c), while GCN-HC displays the thinner flat architectures (Fig. 3d). The highcrystalline structure of GCN-HC could be further verified by high-resolution TEM (HRTEM). The crystal lattice of GCN-HC is obvious in the HRTEM image (Fig. 3f), which is distinctly different with the subcrystalline GCN-B (Fig. 3e). The lattice distance is around 0.33 nm, corresponding to the (002) plane of graphitic structure GCN-HC [37,48]. Moreover, the thickness of GCN-B and GCN-HC samples were measured by AFM analyse.

Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Fig. 5 e (a) FT-IR spectra and (b) survey XPS spectra of as-prepared GCN-B and GCN-HC. (c) High-resolution C1s and (d) N1s spectra of the samples.

As depicted in Fig. 4a and b, GCN-B has the agglomerated bulky structure with a thick thickness of about 80 nm. As we expect, GCN-HC possesses the uniform plate-like architectures with a more thin thickness of approximately 27 nm (Fig. 4c and d). This result is consistent with the SEM and TEM images, demonstrating that the GCN-HC with plate-like nanostructure was successfully prepared by a simple onestep rapid polymerization strategy. To further study the chemical structure and elemental state of the photocatalysts, the samples are performed by FTIR and XPS. As shown in Fig. 5a, the characteristic absorption bands of both GCN-B and GCN-HC samples display the similar FT-IR spectra, suggesting their same chemical structures. The FT-IR spectra are divided to three peaks at 3000-3500 cm1 for NeH or OeH stretching, 1200-1700 cm1 for stretching modes of CN heterocycles, and 807 cm1 for stretching of heptazine units, respectively [21,51,58,59]. Meanwhile, the full survey XPS spectrum of both GCN-B and GCN-HC are only composed of C, N, and O elements (Fig. 5b), demonstrating their same elements state. It should be pointed out that the weaker O1s peak is related to the absorbed H2O or CO2 on the product surface [60,61]. For high-resolution C1s spectrum (Fig. 5c), the samples are fitted with two peaks at binding energies of 284.86 and 288.4 eV, ascribing to the graphitic carbon atoms and sp2hybridized carbon in the aromatic ring, respectively. Moreover, both GCN-B and GCN-HC show the similar highresolution N1s spectra (Fig. 5d), which are deconvoluted into three peaks at 398.6, 399.8, and 401.1 eV, assigning to the sp2-

hybridized nitrogen (C]NeC), tertiary nitrogen [N-(C)3], and amino functional groups (CeNeH), respectively [16,19,34,60e64]. The Brunauer-Emmett-Teller (BET) surface area of asprepared samples were measured by N2 adsorption/desorption isotherms. Fig. 6 depicts the typical type-IV isotherms featured with the H3 hysteresis loops in 0.8e1.0 relative pressure, indicating the presence of mesopores in both GCN-B

Fig. 6 e N2 adsorption-desorption isotherms of the assamples. The insert is their pore size distribution curves.

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Fig. 7 e (a) The UVevis absorption spectra and (b) Tauc plots of GCN-B and GCN-HC. (c) Mott-Schottky plots and (d) electronic band structures of the products.

Fig. 8 e (a) Time courses of photocatalytic H2 evolution under visible-light irradiation (l > 420 nm). (b) H2 evolution rates of as-synthesized samples under visible-light (l > 420 nm) and full arc irradiation. (c) Photocatalytic recycle stability test of GCN-HC under visible-light irradiation (l > 420 nm). (d) XRD patterns of the GCN-HC sample before and after five times visible-light-driven photocatalytic reactions. Please cite this article as: Wang L et al., Rapid polymerization synthesizing high-crystalline g-C3N4 towards boosting solar photocatalytic H2 generation, International Journal of Hydrogen Energy, https://doi.org/10.1016/j.ijhydene.2019.12.168

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Fig. 9 e (a) EIS and (b) PL spectra of as-prepared GCN-B and GCN-HC. (c) Photocurrent spectra of as-synthesized GCN-B and GCN-HC. (d) Time-resolved PL spectra of as-fabricated GCN-B and GCN-HC.

and GCN-HC products [65]. The BET surface area of GCN-B and GCN-HC photocatalysts are calculated to be 19.37 and 21.87 m2/g, respectively. The slight increasing in the specific surface area of GCN-HC would be beneficial for its catalytic applications. Furthermore, the pore size distribution plots (inset in Fig. 6) illustrate that the average pore size of GCN-B and GCN-HC are determined to be 13.14 and 13.54 nm, respectively. The light absorption properties of as-prepared samples were tested by UVevis diffuses reflectance spectra. As illustrated in Fig. 7a, both GCN-B and GCN-HC products show a broad light absorption from the UV to the visible-light region, and the absorption edge of GCN-HC displays a significantly blue shift as compared to GCN-B. Simultaneously, the band gaps of the GCN-HC and GCN-B were calculated by the Tauc plots and estimated to be 2.48 and 2.35 eV, respectively

(Fig. 7b). The blue shift of the absorption edge and the increased of band gap are caused by the quantum size effect of thinner thickness GCN-HC [19,66,67]. In addition, the conduction band (CB) positions of the products were carried out by Mott-Schottky plots (Fig. 7c). The CB values of GCN-B and GCN-HC are determined to be 0.52 and 0.69 eV, thus their valence band (VB) levels were calculated to be 1.96 and 1.66 eV, respectively. Based on the density functional theory of g-C3N4 materials [68e70], the different CB and VB positions of GCN-B and GCN-HC may be due to their distinct optical absorption intensities, altered band gaps values as well as unequal CN layer thickness. The electronic band structures of the asfabricated products are schematically shown in Fig. 7d. It can be clearly found that the band gaps of both GCN-B and GCN-HC can well satisfy the photoredox potentials for water splitting, and the CB position of GCN-HC is more negative than

Table 1 e The comparison of photocatalytic H2-evolution performance with some previously reported geC3N4ebased heterojunctions photocatalysts. geC3N4ebased samples GCN-HC g-C3N4/InVO4 g-C3N4/Cr2O3 g-C3N4/Ta2O5 g-C3N4/ZneTi LDH g-C3N4/t-ZrO2 g-C3N4/WS2

Synthesis methods

HER mmol/g/h

Ref.

One-step thermal polymerization of melamine at 550  C Introducing g-C3N4 sheets to InVO4 precursor by hydrothermal reaction One-pot pyrolysis of melamine with CrCl3$6H2O Thermal polymerization of melamine with purchased Ta2O5 Introducing g-C3N4 nanosheets to Zn(NO3)2$6H2O and TiCl4 precursors by hydrothermal reaction Thermal polymerization of melamine with Zr(NO3)4$5H2O Calcination of thiourea with Na2WO4$2H2O

339.4 212 109 36.4 161.9

Our work [74] [75] [76] [77]

722.5 154

[78] [79]

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the GCN-B, suggesting the enlarged protons thermodynamic driving force would easily lead to the photocatalytic H2 generation [21,71e73]. The photocatalytic properties of the products were studied by water splitting for photocatalytic H2 generation, which triethanolamine used as a hole sacrificial agent and Pt nanoparticles as a cocatalyst. As shown in Fig. 8a, GCN-B exhibits a low photocatalytic H2-genration activity, which is much lower than the GCN-HC. A comparison of the H2 evolved rate (HER) of as-prepared GCN-B and GCN-HC is displayed in Fig. 8b. Under visible-light irradiation (l > 420 nm), it can be obviously seen that the HER of GCN-B is 165.1 mmol g1 h1, and the HER of GCN-HC greatly improves to 339.4 mmol g1 h1, which is approximately 2.06 times higher than GCN-B powders. Under full arc irradiation, the HER of GCN-HC reaches up to 1031.3 mmol g1 h1, which is also 1.49 times higher than GCN-B powders. Table 1 displays the photocatalytic H2-evolution performance of the recently reported geC3N4ebased heterojunctions photocatalysts as comparison with our work [74e79]. It can be found that the HER of GCN-HC is higher than some of the reported g-C3N4 heterojunctions. Meanwhile, the apparent quantum yield of GCN-HC is calculated to be 3.8% at l ¼ 420 nm. Subsequently, the stability of the GCN-HC photocatalyst was evaluated by five times cycle experiments under visible light. As presented in Fig. 8c, GCN-HC displays no significant deactivation H2 evolution performance after 20 h irradiation, demonstrating its excellent photochemical stability. More encouraging, the XRD patterns intensity and peak position of GCN-HC before and after photocatalysis have no obviously changed (Fig. 8d), which is beneficial for its practical applications and further proved that the GCNHC is an efficient and stable photocatalyst. Therefore, the results suggest that the GCN-HC derived from the one-step rapid polymerization strategy can be acted as a promising candidate for photocatalytic solar-to-H2 conversion. As is known that the photoexcited electron-hole pair's transfer efficiency is one of the main factors influence on the photocatalytic activity. Thus, the EIS, PL and time resolved PL analyses were applied to estimate the photoexcited charge carriers transfer efficiency. As presented in Fig. 9a, the GCNHC has a much smaller EIS arc radius as compared to GCNB, revealing the faster separation rate of charge migration [20,27,80e82]. Meanwhile, GCN-HC exhibits a much stronger PL quenching with respect to GCN-B (Fig. 9b), further demonstrating the recombination rate of photoinduced charge is suppressed [83e85]. Moreover, the better charge transfer capability of GCN-HC is also reflected in the increased photocurrent density much higher than that of GCN-B (Fig. 9c). Additionally, Fig. 9d illustrates the time-resolved PL decay spectra by double exponential fitting. It can be found that the average PL lifetimes of GCN-B and GCN-HC products are calculated to be 21.0 and 17.6 ns, respectively. The decreased PL lifetime proves the presence of charge separation at the GCN-HC interface, which is favorable for the photocatalytic reaction [86]. Based on the above results, the remarkably enhanced photocatalytic activity of GCN-HC is originated from the several factors: (i) The more negative CB position of GCN-HC has an enlarged protons thermodynamic driving force,

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which would easily lead to the photocatalytic H2 generation; (ii) GCN-HC with high-crystalline structure possesses the faster photoexcited electron-hole pair's separation as compared to GCN-B, which would greatly benefit for the photoreactivity; (iii) GCN-HC shows more thinner thickness and slightly enlarged surface area in comparison with GCN-B, which would contribute to the mass transfer and increasing the catalytic reactive sites.

Conclusions In summary, for the first time, we report a simple one-step rapid polymerization route to directly fabricate the GCN-HC photocatalyst. Compared to the GCN-B powders derived from common polymerization process, the GCN-HC with fewer structural defects has a faster photoexcited charge transfer efficiency and stronger Hþ thermodynamic driving force. As a result, the as-prepared GCN-HC not only shows a significantly promoted photocatalytic H2-generation performance under visible light, but also exhibits an excellent photostability. Our work provides a new and available onestep synthetic strategy for the scalable synthesis of high performance GCN-HC photocatalyst. Apart from the photoreduction of water, the GCN-HC would be as a promising catalyst applications in pollutants photodegradation, CO2 reduction, and optoelectronic devices.

Acknowledgements This work would like to acknowledge the Youth Talent Lifting Project of Jilin Province (181907), the National Natural Science Foundation of China (31971616), the Science and Technology Innovation Development Plan of Jilin City (201830811), the Natural Science Foundation Project of Jilin Provincial Science and Technology Development Plan (20190201277JC), and the Science Development Project of Jilin City (20190104120).

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