Construction and performance of CdS/MoO_(2)@Mo_(2)C-MXene photocatalyst for H_(2) production

Nowadays,photocatalytic technologies are regarded as promising strategies to solve energy problems,and various photocatalysts have been synthesized and explored.In this paper,a novel CdS/MoO_(2)@Mo_(2)C-MXene photocatalyst for H_(2)production was constructed by a two-step hydrothermal method,where MoO_(2)@Mo_(2)C-MXene acted as a binary co-catalyst.In the first hydrothermal step,MoO_(2)crystals with an egged shape grew on the surface of two-dimensional(2D)Mo_(2)C MXene via an oxidation process in HCl aqueous solution.In the second hydrothermal step,CdS nanorods were uniformly assembled on the surface of MoO_(2)@Mo_(2)C-MXene in ethylenediamine with an inorganic cadmium source and organic sulfur source.The CdS/MoO_(2)@Mo_(2)C-MXene composite with MoO_(2)@Mo_(2)C-MXene of 5 wt%exhibits an ultrahigh visible-light photocatalytic H_(2)production activity of 22,672μmol/(g·h),which is~21%higher than that of CdS/Mo_(2)C-MXene.In the CdS/MoO_(2)@Mo_(2)C-MXene composite,the MoO_(2)with metallic nature separates CdS and Mo_(2)C MXene,which acts as an electron-transport bridge between CdS and Mo_(2)C MXene to accelerate the photoinduced electron transferring.Moreover,the energy band structure of CdS was changed by MoO_(2)@Mo_(2)C-MXene to suppress the recombination of photogenerated carriers.This novel compound delivers upgraded photocatalytic H_(2)evolution performance and a new pathway of preparing the low-cost photocatalyst to solve energy problems in the future.