Efficient photocatalytic hydrogen production over copper-molybdate coupled with Meso-TiO2 under low concentration of sacrificial agent

Photocatalytic production of solar energy conversion fuels is a major research area for solar energy conversion. TiO2, a widely studied semiconductor in photocatalytic water splitting, faces certain limitations since it is only responsive to ultraviolet light and inadequate intrinsic activity for hydrogen production. Two composite photocatalysts Cu1/TiO2 and Cu3/TiO2 were prepared for H2 evolution by confining copper-molybdate co -catalysts (CuMoO4 and Cu3Mo2O9) within the mesoporous space of TiO2, which both exhibit wider absorption edges than that of blank Meso-TiO2. The use of sacrificial donors is unavoidable in most photocatalytic systems. However, it would be highly desirable to use small amounts of sacrificial donors to reduce the cost and carbon emission. The amount of sacrificial reagent in the photocatalytic system was explored in depth. Under light illumination, Cu1/ TiO2 and Cu3/TiO2 exhibit relatively high photocatalytic H2 evolution activities, which are 32.3 and 73.8 folds higher than those of blank Meso-TiO2 at very small usage amount of sacrificial reagent (0.1% v/v TEOA). By various characterizations, the enhancement of activity could be attributed to the contribution of co -catalysts, which are composed as copper molybdate undecomposed and CuO derived from the partial decomposition of copper molybdate. During this process, the interactions among TiO2, copper-molybdate and the newly formed CuO construct a dual -channel electron transfer system (p -n heterojunction and co -catalyst). This work provides new idea for exploring efficient photocatalytic hydrogen production system under low concentration of sacrificial agent.