Edge-Rich Bicrystalline 1T/2H-MoS2 Cocatalyst-Decorated {110} Terminated CeO2 Nanorods for Photocatalytic Hydrogen Evolution

Developing all-solid-state Z-scheme systems with highly active photocatalysts are of huge interest in realizing long-term solar-to-fuel conversion. Here we reported an innovative hybrid of {110}oriented CeO2 nanorods with edge-enriched bicrystalline 1T/2H-MoS2 coupling as efficient photocatalysts for water splitting. In the composites, the metallic 1T phase acts as an excellent solid state electron mediator in the Z-scheme, while the 2H phase and CeO2 are the adsorption sites of the photosensitizer and reactant (H2O), respectively. Through optimal structure and phase engineering, 1T/2H-MoS2@CeO2 heterojunctions simultaneously achieve high charge separation efficiency, proliferated density of exposed active sites, and excellent affinity to reactant molecules, reaching a superior hydrogen evolution rate of 73.1 mu mol/h with an apparent quantum yield of 8.2% at 420 nm. Furthermore, density functional theory calculations show that 1T/2H-MoS2@CeO2 possesses the advantages of intensive electronic interaction from the built-in electric field (negative MoS2 and positive charged CeO2) and reduced H2O adsorption/dissociation energies. This work sheds light on the design of on-demand noble-metal-free Z-scheme heterostructures for solar energy conversion.

Automated summary

By developing an innovative hybrid photocatalyst, this study has achieved high charge separation efficiency and superior hydrogen evolution rate through optimal structure and phase engineering. The design provides a new approach for solar energy conversion.