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Oxygen-contained amorphous MoSx cocatalyst by one-step photodeposition to enhance H-adsorption affinity for efficient photocatalytic H2 generation

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Abstract

Traditional bulk MoS2 as an effective H2-evolution cocatalyst is mainly subjected to the weak hydrogen-adsorption ability of high-porpotion saturated S, resulting in a slow interfacial H2-evolution reaction. In this paper, an efficient strategy for enhancing hydrogen adsorption of saturated S by manipulating electron density through O atoms is proposed to boost photocatalytic performance of CdS. Simultaneously, amorphization of MoS2 can further increase the unsaturated active S sites. Herein, oxygen-contained amorphous MoSx (a-MoOSx) nanoparticles (10–30 nm) were tightly loaded on the CdS surface through a mild photoinduced deposition method by using (NH4)2[MoO(S4)2] solution as the precursor at room temperature. The photocatalytic H2-evolution result showed that the a-MoOSx/CdS performed the superior H2-production activity (382 µmol·h−1, apparent quantum efficiencies (AQE) = 11.83%) with a lot of visual H2 bubbles, which was 54.6, 2.5, and 5.1 times as high as that of CdS, MoSx/CdS, and annealed a-MoOSx/CdS, respectively. Characterizations and density functional theory (DFT) calculations revealed the mechanism of improved H2-evolution activity is that the O heteroatom in amorphous MoOSx can enhance the atomic H-adsorption ability by manipulating the electron density to form electron-deficient S(2−δ)− sites. This study provides a new idea to improve the efficiency and number of H2-evolution active sites for developing efficient cocatalysts in the field of photocatalytic hydrogen evolution.

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 22178275) and the Natural Science Foundation of Hubei Province of China (No. 2022CFA001).

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  1. School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, China

    Pinsi Deng, Ping Wang, Xuefei Wang, Feng Chen & Huogen Yu

  2. Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, 430074, China

    Huogen Yu

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  1. Pinsi Deng
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Oxygen-contained amorphous MoSx cocatalyst by one-step photodeposition to enhance H-adsorption affinity for efficient photocatalytic H2 generation

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Deng, P., Wang, P., Wang, X. et al. Oxygen-contained amorphous MoSx cocatalyst by one-step photodeposition to enhance H-adsorption affinity for efficient photocatalytic H2 generation. Nano Res. 16, 8977–8986 (2023). https://doi.org/10.1007/s12274-023-5629-7

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