Visible-light induced hydrogen generation with ZnO/NiO/Cd1-xZnxS (x=0.0, 0.2) heterostructures

Abstract

ZnO/NiO/Cd1-xZnxS (x=0.0, 0.2) heterostructures have been prepared by a simple solution-based procedure using ZnO/NiO heterostructures prepared by different methods. We obtain good hydrogen evolution activity only with ZnO/NiO heterostructures and not with Zn1-yNiyO solid solutions. The hydrogen evolution activities of ZnO/NiO/CdS and ZnO/NiO/Cd1-xZnxS are 2.2 and 8.2 mmol/h/g respectively with apparent quantum yields of 2.3 and 14% under visible-light irradiation. These values of activity are comparable or superior to those obtained with ZnO/Pt/Cd1-xZnxS and ZnO/Au/Cd1-xZnxS heterostructures. With UV-vis irradiation, the activity found with ZnO/NiO/Cd1-xZnxS is 14-17 mmol/h/g with an apparent quantum yield in the range of 12-15%. (C) 2014 Elsevier B.V. All rights reserved.