Fabrication of hierarchical ZnIn2S4OCNO nanosheets for photocatalytic hydrogen production and CO2 photoreduction

Photocatalytic H-2 production and CO2 reduction have attracted considerable attention for clean energy development. In this work, we designed an efficient photocatalyst by integrating lamellar oxygen-doped carbon nitride (CNO) nanosheets into ZnIn2S4 (ZIS) microflowers by a one-step hydrothermal method. A well-fitted 2D hierarchical hybrid heterostructure was fabricated. Under visible light irradiation, the ZIS@CNO composite with 40 wt% CNO (ZC 40%) showed the highest hydrogen evolution rate from water (188.4 mu mol.h(-1)), which was approximately 2.1 times higher than those of CNO and ZIS (88.6 and 90.2 mu mol.h(-1), respectively). Furthermore, the selective CO production rates of ZC 40% (12.69 mu mol.h(-1)) were 2.2 and 14.0 times higher than those of ZIS (5.85 mu mol.h(-1)) and CNO (0.91 mu mol.h(-1)), respectively, and the CH4 production rate of ZC 40% was 1.18 mu mol.h(-1). This enhanced photocatalytic activity of CNO@ZIS is due mainly to the formation of a heterostructure that can promote the transfer of photoinduced electrons and holes between CNO and ZIS, thereby efficiently avoiding recombination of electron-hole pairs. (C) 2020, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.