Enhanced Photocatalytic Performance of a ZnO/CdS Heterostructure for Hydrogen Production and Mixed Dye Degradation

Abstract

AbstractZnO/CdS composite was prepared using a simple one‐step hydrothermal method, and its photocatalytic performance was investigated under different conditions. The photocatalytic efficiency of ZnO/CdS was 6345.04 μmol ⋅ g−1 ⋅ h−1 in H2 production from water splitting using Na2S and Na2SO3 as sacrificial agents. The photocatalytic efficiency of eosin Y‐sensitized ZnO/CdS was 6939.39 μmol ⋅ g−1 ⋅ h−1 when triethanolamine was used as a sacrificial agent. The photocatalytic activity of ZnO/CdS was better than those of pristine ZnO and CdS during H2 evolution. The ZnO/CdS composite also exhibited superior photocatalytic activity compared to pristine ZnO and CdS in the degradation of a mixed dye pollutant. The degradation rates of methylene blue, rhodamine B, and orange G in the mixed dye after 120 min of irradiation were 99.41 %, 92.96 %, and 65.74 %, respectively. Possible mechanisms for photocatalytic H2 production and photocatalytic degradation of organic pollutants have been proposed.