Synergistic effect of rare earth metal Sm oxides and Co1−xS on sheet structure MoS2 for photocatalytic hydrogen evolution

Abstract

The novel composite Sm₂O₃@Co_1−xS/MoS₂ was synthesized by an efficient and easy operation solvothermal process. As a new photocatalyst, it has high photocatalytic activity. The hydrogen evolution amount of the Sm₂O₃@Co_1−xS/MoS₂ catalyst is as high as 448 μmol under visible light irradiation for 5 h, which is about 4 times higher than MoS₂ and still exhibited high photocatalytic stability. The AQEs reached 32.1% at 475 nm. The synergistic effect of rare earth metal Sm oxides and Co_1−xS over MoS₂ sheet for photocatalytic activity and stability were analysed by SEM, TEM, XRD, XPS, UV-vis, and fluorescence spectra etc. The results showed that the deposited Sm₂O₃@Co_1−xS are uniformly dispersed on the MoS₂ sheet, the electron transfer and the charge separation were obviously improved with the aid of Sm₂O₃ and Co_1−xS on the surface of MoS₂. The BET results showed that Sm₂O₃@Co_1−xS/MoS₂ had a greater specific surface area and pore volume, which was beneficial to the adsorption of dye molecules and enhanced the photocatalytic activity. Therefore, rare earth metal Sm oxides might be a potential cocatalyst for the design of a new photocatalyst.