Tracking charge transfer pathways in SrTiO3/CoP/Mo2C nanofibers for enhanced photocatalytic solar fuel production

doi:10.1016/S1872-2067(21)63898-6

Abstract

Abstract:

Photocatalytic solar fuel generation is currently a hot topic because of its potential for solving the energy crisis owing to its low cost and zero-carbon emissions. However, the rapid bulk recombination of photoexcited carrier pairs is a fundamental disadvantage. To resolve this problem, we synthesized a dual cocatalysts system of cobalt phosphide (CoP) and molybdenum carbide (Mo₂C) embedded on strontium titanate (SrTiO₃) nanofibers. Compared with those of pristine SrTiO₃ and binary samples, the dual cocatalysts system (denoted SCM) showed a significant improvement in the hydrogen evolution and CO₂ reduction performance. Further, the structure of SCM effectively promoted spatial charge separation and enhanced the photocatalytic performance. In addition, the Schottky junction formed between the SrTiO₃ and cocatalysts enabled the rapid transfer of photoexcited electrons from SrTiO₃ to the cocatalysts, resulting in effective separation and prolonged photoexcited electron lifetimes. The electron migration route between SrTiO₃and the cocatalysts was determined by in situ irradiation X-ray spectroscopy, and band structures of SrTiO₃ and the cocatalysts are proposed based on results obtained from UV-vis diffraction reflection spectroscopy and ultraviolet photoelectron spectroscopy measurements. On the basis of our results, the dual cocatalysts unambiguously boosts charge separation and enhances photocatalytic performance. In summary, we have investigated the flux of photoexcited electrons in a dual cocatalysts system and provided a theoretical basis and ideas for subsequent research.

Key words: Dual cocatalyst, Electron migration, Schottky junction, Electrospinning, In situ irradiation XPS, Photocatalyst, Solar fuel

Li Wang, Yukun Li, Chao Wu, Xin Li, Guosheng Shao, Peng Zhang. Tracking charge transfer pathways in SrTiO₃/CoP/Mo₂C nanofibers for enhanced photocatalytic solar fuel production[J]. Chinese Journal of Catalysis, 2022, 43(2): 507-518.

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URL: https://www.cjcatal.com/EN/10.1016/S1872-2067(21)63898-6

https://www.cjcatal.com/EN/Y2022/V43/I2/507

Figures/Tables 10

Fig. 1(a) illustrates the synthetic process. XRD is a common characterization method used to determine the crystalline phases of materials. As shown in Fig. 1(b), the distinct diffraction peaks (2θ) at 22.8°, 32.4°, 40.0°, 46.5°, 52.4°, 57.8°, 67.8°, 72.5°, and 77.2° could be indexed to the (100), (110), (111), (200), (210), (211), (220), (300) and (310) lattice planes of SrTiO3, respectively. The XRD pattern of SC-2 is the same as that of pure STO (JCPDS no. 35-0734), indicating that the introduction of CoP did not change the structure of STO, and the diffraction peaks for all STO/CoP NFs can be assigned to cubic SrTiO3. The diffraction peaks of CoP (JCPDS no. 26-0481) and Mo2C (JCPDS no. 35-0787) in SC-2 and SCM, respectively, can be barely seen, indicating that CoP and Mo2C were uniformly and finely distributed. On the basis of previous works [55,56], the (011) facet of CoP is the active site and tends to be more exposed than other facets. After decorating Mo2C on SC-2, the material was carbonized at 800 °C, and the high temperature aided the growth of the CoP crystals. In addition, the high pressure and the introduction of Mo2C may lead to the lattice distortion of CoP, thus the peak had shifted. As a result, the XRD pattern of SCM showed a peak at approximately 31°. Next, we increased the amount of CoP to 12%. The XRD pattern of CoP is shown in Fig. S1(b), and that of Mo2C is shown in Fig. S1(c). By comparison of these XRD patterns, we determined that the STO/CoP NFs and SCM NFs had been synthesized successfully.

Fig. 1. (a) Illustration of the preparation of samples; (b) XRD patterns of STO, SC-2, and SCM.

Fig. 2. SEM (a), TEM (b), and HRTEM (c,d) images of STO; SEM (e), TEM (f), and HRTEM (g,h) images of SCM; (i) Corresponding EDX elemental mapping images of SCM.

Fig. 3. (a) N2 adsorption-desorption isotherms of STO; (b) Comparison of photocatalytic H2 generation over different samples; (c) Cyclic H2 generation tests for SC-2 under simulated solar irradiation; (d) H2 generation rate of samples; (e) XRD patterns of SC-2 before and after cycling tests; (f) Transient photocurrent response of samples; LSV curves (g), PL spectra (h) of SC-2 and STO; (i) TPV curves of SC-2 and STO.

Fig. 4. (a) Comparison of photocatalytic H2 generation over SCM and SC-2; (b) Cycling tests of H2 generation for SCM and SC-2 under solar light irradiation; (c) CO2 reduction reaction activity of STO, SC-2, and SCM; (d) AQE of SCM; (e) Transient photocurrent response of samples; (f,g) LSV curves and EIS plots of SCM, SC-2, and STO; (h) UV-Vis DRS pattern of samples; (i) Plots of (αhν)2 versus the photon energy (hν), where α, h, and ν are the absorption coefficient, Planck’s constant, and light frequency, respectively.

Fig. 5. (a) UPS spectra of STO, CoP, and Mo2C; (b) Band structure of STO, CoP, and Mo2C.

Fig. 6. (a) Working mechanism of ISI-XPS; (b-e) Schematic of the shielding effect of STO and CoP.

Fig. 7. In situ irradiation XPS spectra for Sr 3p (a), Ti 2p (b), Co 2p (c), and P 2s (d).

Fig. 8. (a) XPS survey spectrum of SCM composites and in situ irradiation XPS spectra of Sr 3p (b), Ti 2p (c), Mo 3d (d), Co 2p (e), and P 2s (f).

Fig. 9. Band structures and catalytic mechanism of STO (a), SC-2 (b), and SCM (c).

References

[1]	X. J. Wang, X. Tian, Y. J. Sun, J. Y. Zhu, F. T. Li, H. Y. Mu, J. Zhao, Nanoscale, 2018,10, 12315-12321.
[2]	R. Xiao, C. Zhao, Z. Zou, Z. Chen, L. Tian, H. Xu, H. Tang, Q. Liu, Z. Lin, X. Yang, Appl. Catal. B, 2020,268, 118382.
[3]	D. Friedmann, A. F. Lee, K. Wilson, R. Jalili, R. A. Caruso, J. Mater. Chem. A, 2019,7, 10858-10878.
[4]	H. Gao, P. Zhang, J. Zhao, Y. Zhang, J. Hu, G. Shao, Appl. Catal. B, 2017,210, 297-305.
[5]	Q. Zheng, Y. Cao, N. Huang, R. Zhang, Y. Zhou, Acta Phys.-Chim. Sin., 2020,37, 2009063.
[6]	X. Yue, S. Yi, R. Wang, Z. Zhang, S. Qiu, Nano Energy, 2018,47, 463-473.
[7]	J. Pan, S. Shen, W. Zhou, J. Tang, H. Ding, J. Wang, L. Chen, C. T. Au, S. F. Yin, Acta. Phys.-Chim. Sin., 2020,36, 1905068.
[8]	W. Zhong, D. Gao, H. Yu, J. Fan, J. Yu, Chem. Eng. J., 2021,419, 129652.
[9]	S. Anantharaj, S. R. Ede, K. Sakthikumar, K. Karthick, S. Mishra, S. Kundu, ACS Catal., 2016,6, 8069-8097.
[10]	A. Kudo, Y. Miseki, Chem. Soc. Rev., 2009,38, 253-278.
[11]	Q. Liu, J. Huang, H. Tang, X. Yu, J. Shen, J. Mater. Sci. Technol., 2020,56, 196-205.
[12]	C. Diao, H. Liu, Z. Li, Z. Yao, H. Hao, M. Cao, J. Alloys Compd., 2020,845, 155636.
[13]	Y. Luo, B. Deng, Y. Pu, A. Liu, J. Wang, K. Ma, F. Gao, B. Gao, W. Zou, L. Dong, Appl. Catal. B, 2019,247, 1-9.
[14]	L. Ren, X. Yi, L. Tong, W. Zhou, D. Wang, L. Liu, J. Ye, Appl. Catal. B, 2020,279, 119352.
[15]	N. Xiao, S. Li, X. Li, L. Ge, Y. Gao, N. Li, Chin. J. Catal., 2020,41, 642-671.
[16]	P. Kuang, J. Low, B. Cheng, J. Yu, J. Fan, J. Mater. Sci. Technol., 2020,56, 18-44.
[17]	A. Fujishima, K. Honda, Nature, 1972,238, 37-38.
[18]	Y. Kim, M. Watanabe, J. Matsuda, J. T. Song, A. Takagaki, A. Staykov, T. Ishihara, Appl. Catal. B, 2020,278, 119292.
[19]	D. Gao, R. Yuan, J. Fan, X. Hong, H. Yu, J. Mater. Sci. Technol., 2020,56, 122-132.
[20]	Y. Li, P. Zhang, D. Wan, C. Xue, J. Zhao, G. Shao, Appl. Surf. Sci., 2020,504, 144361.
[21]	K. Li, S. Zhang, Y. Li, J. Fan, K. Lv, Chin. J. Catal., 2021,42, 3-14.
[22]	Y. Chen, Y. Wang, J. Fang, B. Dai, J. Kou, C. Lu, Y. Zhao, Chin. J. Catal., 2021,42, 184-192.
[23]	J. T. Lee, Y. J. Chen, E. C. Su, M. Y. Wey, Int. J. Hydrogen Energy, 2019,44, 21413-21423.
[24]	G. Zhang, S. Sun, W. Jiang, X. Miao, Z. Zhao, X. Zhang, D. Qu, D. Zhang, D. Li, Z. Sun, Adv. Energy Mater., 2017,7, 1600932.
[25]	L. Qiao, W. Li, H. Xiao, H. M. Meyer, X. Liang, N. V. Nguyen, W. J. Weber, M. D. Biegalski, ACS Appl. Mater. Interfaces, 2014,6, 14338-14344.
[26]	W. Li, X. Chu, F. Wang, Y. Dang, X. Liu, X. Wang, C. Wang, Appl. Catal. B, 2021,288, 120034.
[27]	H. Hu, L. Zeng, Z. Li, T. Zhu, C. Wang, Chin. J. Catal., 2021,42, 1345-1351.
[28]	Z. Sun, X. Yang, X. F. Yu, L. Xia, Y. Peng, Z. Li, Y. Zhang, J. Cheng, K. Zhang, J. Yu, Appl. Catal. B, 2021,285, 119790.
[29]	P. Zhang, Z. Li, S. Zhang, G. Shao, Energy Environ. Mater., 2018,1, 5-12.
[30]	S. Zhang, P. Zhang, R. Hou, B. Li, Y. Zhang, K. Liu, X. Zhang, G. Shao, J. Energy Chem., 2020,47, 281-290.
[31]	Q. Sun, Z. Yu, R. Jiang, Y. Hou, L. Sun, L. Qian, F. Li, M. Li, Q. Ran, H. Zhang, Nanoscale, 2020,12, 19203-19212.
[32]	C. Zhang, Y. Zhou, W. Wang, Y. Yang, C. Zhou, L. Wang, L. Lei, D. He, H. Luo, D. Huang, Appl. Surf. Sci., 2020,527, 146757.
[33]	Y. Jia, Z. Wang, X. Q. Qiao, L. Huang, S. Gan, D. Hou, D. S. Li, Appl. Surf. Sci., 2021,554, 149649.
[34]	Q. Yue, Y. Wan, Z. Sun, X. Wu, Y. Yuan, P. Du, J. Mater. Chem. A, 2015,3, 16941-16947.
[35]	J. Tian, Q. Liu, A. M. Asiri, X. Sun, J. Am. Chem. Soc., 2014,136, 7587-7590.
[36]	E. J. Popczun, J. R. McKone, C. G. Read, A. J. Biacchi, A. M. Wiltrout, N. S. Lewis, R. E. Schaak, J. Am. Chem. Soc., 2013,135, 9267-9270.
[37]	Y. Ge, X. Qin, A. Li, Y. Deng, L. Lin, M. Zhang, Q. Yu, S. Li, M. Peng, Y. Xu, X. Zhao, M. Xu, W. Zhou, S. Yao, D. Ma, J. Am. Chem. Soc., 2021,143, 628-633.
[38]	R. Zhao, H. Wang, N. Gao, R. Liu, T. Guo, J. Wu, T. Zhang, J. Li, J. Du, T. Asefa, Small Methods, 2019,4, 1900597.
[39]	P. Tan, A. Zhu, Y. Liu, Y. Ma, W. Liu, H. Cui, J. Pan, Inorg. Chem. Front., 2018,5, 679-686.
[40]	J. Wang, W. Cui, Q. Liu, Z. Xing, A. M. Asiri, X. Sun, Adv. Mater., 2016,28, 215-230.
[41]	X. Ren, S. Wei, Q. Wang, L. Shi, X. S. Wang, Y. Wei, G. Yang, D. Philo, F. Ichihara, J. Ye, Appl. Catal. B, 2021,286, 119924.
[42]	S. Tang, Y. Xia, J. Fan, B. Cheng, J. Yu, W. Ho, Chin. J. Catal., 2021,42, 743-752.
[43]	J. Liu, P. Wang, J. Fan, H. Yu, J. Yu, Nano Res., 2021,14, 1095-1102.
[44]	H. Hou, X. Zhang, Chem. Eng. J., 2020,395, 125030.
[45]	H. Xu, R. Xiao, J. Huang, Y. Jiang, C. Zhao, X. Yang, Chin. J. Catal., 2021,42, 107-114.
[46]	A. Meng, L. Zhang, B. Cheng, J. Yu, Adv. Mater., 2019,31, 1807660.
[47]	P. Zhang, C. Xue, Y. Li, S. Guo, X. Zhang, P. Zhang, G. Shao, Chem. Eng. J., 2021,404, 126497.
[48]	J. Low, B. Dai, T. Tong, C. Jiang, J. Yu, Adv. Mater., 2019,31, 1802981.
[49]	Y. Sun, C. Xue, L. Chen, Y. Li, S. Guo, Y. Shen, F. Dong, G. Shao, P. Zhang, Sol. RRL., 2020,5, 2000722.
[50]	Y. Xia, B. Cheng, J. Fan, J. Yu, G. Liu, Small, 2019,15, 1902459.
[51]	K. Liu, X. Zhang, F. Miao, Z. Wang, S. Zhang, Y. Zhang, P. Zhang, G. Shao, Small, 2021,17, 2100065.
[52]	P. Wang, Y. Mao, L. Li, Z. Shen, X. Luo, K. Wu, P. An, H. Wang, L. Su, Y. Li, S. Zhan, Angew. Chem. Int. Ed., 2019,58, 11329-11334.
[53]	B. He, C. Bie, X. Fei, B. Cheng, J. Yu, W. Ho, A. A. Al-Ghamdi, S. Wageh, Appl. Catal. B, 2021,288, 119994.
[54]	S. Guo, Y. Li, C. Xue, Y. Sun, C. Wu, G. Shao, P. Zhang, Chem. Eng. J., 2021,419, 129213.
[55]	H. Li, X. Zhao, H. Liu, S. Chen, X. Yang, C. Lv, H. Zhang, X. She, D. Yang, Small, 2018,14, 1802824.
[56]	Y. Liu, J. Zhang, X. Li, Z. Yao, L. Zhou, H. Sun, S. Wang, Energy Fuels, 2019,33, 11663-11676.
[57]	F. Miao, N. Lu, P. Zhang, Z. Zhang, G. Shao, Adv. Funct. Mater., 2019,29, 1808994.
[58]	S. Zhang, Y. Zhang, G. Shao, P. Zhang, Nano Res., 2021, https://doi.org/10.1007/s12274-021-3319-x.
[59]	Y. Zhang, P. Zhang, B. Li, S. Zhang, K. Liu, R. Hou, X. Zhang, S. R. P. Silva, G. Shao, Energy Storage Mater., 2020,27, 159-168.
[60]	Y. Zhang, P. Zhang, Z. Wang, N. Li, S. Silva, G. Shao, InfoMat, 2021,3, 790-803.
[61]	Z. Xiang, H. Guan, B. Zhang, Y. Zhao, J. Am. Ceram. Soc., 2020,104, 504-513.
[62]	P. Zhang, Y. Li, Y. Zhang, R. Hou, X. Zhang, C. Xue, S. Wang, B. Zhu, N. Li, G. Shao, Small Methods, 2020,4, 2000214.

Tracking charge transfer pathways in SrTiO₃/CoP/Mo₂C nanofibers for enhanced photocatalytic solar fuel production

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