Coating Hollow Carbon Nitride Nanospheres with Porous WO3 Shells to Construct Z‐Scheme Heterostructures for Efficient Photocatalytic Water Oxidation

Abstract Three‐dimensional (3D) Z‐scheme WO 3 @HCNS hollow nanohybrids with intimate interfacial contacts are constructed by assembling porous WO 3 shells on the outer surface of hollow carbon nitride spheres (HCNS). The structure, morphology, optical/electric and electrocatalytic properties of the WO 3 @HCNS heterostructures are systematically studied, and their photocatalytic performance is evaluated by water oxidation to generate oxygen under visible light (λ>420 nm). The optimal WO 3 @HCNS composite exhibits a high oxygen evolution rate (OER) of 23 μmol h −1 , which is about 20‐fold that of pristine HCNS (OER=1.2 μmol h −1 ). The superior performance of WO 3 @HCNS is mainly attributed to the unique Z‐scheme hollow heterostructures with strongly coupled interfaces, which powerfully promotes the separation and migration of charge carriers, and the shuttling of mass transportation. The work may inspire future works on fabrication of nanoscale hollow carbon nitride‐based Z‐schematic heterostructures with tailored shells and tight junctions as high‐efficiency platforms for photocatalytic H 2 O splitting.