Highly efficient visible-light-driven photocatalytic hydrogen generation by immobilizing CdSe nanocrystals on ZnCr-layered double hydroxide nanosheets

摘要

Mesoporous CdSe/ZnCr-LDH nanohybrids were synthesized by mixing the suspensions containing cationic ZnCr-LDH nanosheets and anionic CdSe nanosol. It was revealed that the CdSe nanocrystals were immobilized on the ZnCr-layered double hydroxide 2D nanosheets. The strong electronic coupling between the two components in the formed heterostructured nanohybrids remarkably suppressed the photogenerated electron-hole recombination. The as-prepared nanohybrids displayed significantly enhanced photocatalytic activity. When the CdSe content was 30 wt%, the H-2-evolution rate was 2196 mu mol h(-1).g(-1) with a quantum efficiency of 51.3% under visible-light irradiation, which is far superior to that of its parent ZnCr-LDH (18 mu mol h(-1).g(-1)). The present findings demonstrate that the self-assembly of CdSe-LDHs is quite effective in synthesizing novel LDHs-based visible-light photocatalyst with high performance in hydrogen evolution from water splitting. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.