Fabrication of CuMnO2/XMoO4 (X=Ni, Co, Fe) heterostructure for hydrogen evolution under visible light irradaiation.

CuMnO 2 /XMoO 4 (X=Ni, Co, Fe) is a novel high-efficiency photocatalyst, which was synthesized by electrostatic self-assembly method. Under visible light irradiation, by comparing with other eighth main group metals (Fe, Co), it was found by experimental study that adding 30 mg of CuMnO 2 to 100 mg of NiMoO 4 (CuMnO 2 /NiMoO 4 -30%), it has the best hydrogen evolution effect up to 300 μ mol, which is 1.49 and 2.88 times more effective than CuMnO 2 /CoMoO 4 and CuMnO 2 /FeMoO 4 respectively. Meanwhile, the hydrogen evolution yield of CuMnO 2 /NiMoO 4 was about 4 times that of CuMnO 2 and NiMoO 4. The photoelectrochemical and time-resolved fluorescence experiments confirmed the excellent charge separation efficiency of the composite catalyst, and the linear voltammetry curve showed that the composite catalyst had the characteristics of high current response. When CuMnO 2 is loaded on NiMoO 4 , CuMnO 2 /NiMoO 4 exhibits excellent photocatalytic activity due to the formation of Type I heterojunction, which promote charge transfer and effectively improve the separation of electrons and holes. This experiment provides a simple and feasible idea for the study of composite catalysts with high catalytic activity. • The heterojunction between CuMnO 2 and NiMoO 4 has good stability. • Dispersion of CuMnO 2 on NiMoO 4 is important for the HER activity. • Discussion on electron transfer path and hydrogen evolution mechanism. [ABSTRACT FROM AUTHOR]