Hydrothermal synthesis of Mn${}_3$O${}_4$/CoS${}_2$ as a promising photocatalytic material for boosting visible-light photocatalytic hydrogen production

Photocatalytic hydrogen evolution has received extensive attention for energy conversion and storage of clean energy. Herein, the composite catalyst Mn${}_3$O${}_4$/CoS${}_2$ is successfully prepared by a hydrothermal method. Photocatalytic hydrogen evolution experiments are conducted by adjusting the amount of Mn${}_3$O${}_4$. The results show that the composite photocatalyst Mn${}_3$O${}_4$/CoS${}_2$ has higher photocatalytic hydrogen evolution performance. The hydrogen production of the 50 mg Mn${}_3$O${}_4$/CoS${}_2$ composite catalyst at 5 h is 14.95 times and 1.60 times that of pure Mn${}_3$O${}_4$ and CoS${}_2$, respectively, indicating that the 50 mg Mn${}_3$O${}_4$/CoS${}_2$ composite catalyst has good photocatalytic stability. In addition, the structure, morphology, and composition of the prepared catalysts are characterized by scanning electron microcopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), electrochemical and PL techniques. Compared with Mn${}_3$O${}_4$ and CoS${}_2$, the photocatalytic response of the 50 mg Mn${}_3$O${}_4$/CoS${}_2$ composite catalyst is significantly enhanced, the current density is increased, the fluorescence quenching efficiency is accelerated, and the pore volume and pore size are increased. Therefore, the composite catalyst can accelerate the separation and transfer of photogenerated electrons and holes and improve the photocatalytic efficiency. (© 2021 Wiley‐VCH GmbH)