Reversed configuration of photocatalyst to exhibit improved properties of basic processes compared to conventional one

Abstract

Performances of semiconductor photocatalysts are integrally determined by efficiencies of basic processes such as light absorption, charge separation and surface catalysis, but conventional configurations of photocatalysts normally suffers from the competition of light absorption originating from cocatalyst deposition and limited interface charge separation between the photocatalyst and cocatalyst. Herein we give the first proof-of-concept illustration that a reversed configuration of photocatalysts with a core/shell structure of microsized Mo2N cocatalysts and nanosized CdS photocatalysts, which exhibits superior solar hydrogen production to the conventional configuration with nanosized Mo2N cocatalysts deposited on the surface of CdS photocatalysts. It is revealed that the reversed configuration outperforms the conventional one in all areas of light absorption, charge separation and surface catalysis. Strikingly, the special core/shell structure introduced here can well avoid the competition of light absorption by cocatalysts and make an effective confinement effect to promote the surface catalysis of Mo2N. Our finding provides an alternative strategy to improve performances of photocatalysts.