Morphology controlling strategy of ZnS/CeO2 catalysts to enhance the photocatalytic performance for hydrogen production

Abstract

Semiconductor photocatalysts have been utilized to convert solar energy into hydrogen. However, CeO₂ has been rarely reported as a photocatalyst for hydrogen production on account of the rapid photoelectron-hole pair recombination and limited visible light adsorption capacity. In this work, we present the morphology controlling strategy on the purpose of preparing efficient composite semiconductor photocatalysts of CeO₂ with regular shape and reliable performance. The synthesized photocatalysts ZnS/CeO₂ with completely different morphologies structure (ZnS/CeO₂ solid spheres and ZnS/CeO₂ hollow dodecahedra) were obtained by a similar method. The results show that with the expansion of the visible light absorption range and the increase of nano pore porosity, the two photocatalysts ZnS/CeO₂ can afford more active sites and promote the transfer of photogenerated electrons-holes, thus effectively improving the hydrogen production efficiency. Besides, both of the photocatalysts ZnS/CeO₂ exhibit the long term (25 ​h) stability that also indicates a great potential in the photocatalytic water splitting for hydrogen evolution. This work provides a new idea and research method for further research on hydrogen production from photolysis of water.