PdS-modified CdS/NiS composite as an efficient photocatalyst for H2 evolution in visible light

Incorporation of PdS into a NiS-modified CdS catalyst further increases the photo-catalytic H-2 evolution rate from 45 mL h(-1) to 84 mL h(-1) under visible light irradiation using lactic acid as the sacrificial reagent. In the composite catalyst, NiS serves as the H-2 evolution cocatalyst while PdS behaves as the hole consumption cocatalyst, which accelerates the transfer of the photo-generated holes and serves as the active sites for the reaction between holes and lactic acid, thus enhancing the separation of the pairs. Furthermore, PdS also enhances the overall light absorption capability and increases the photocurrent intensity and lowers the resistance of the interface layer for the charge transfer in the composite catalyst. (C) 2013 Elsevier B.V. All rights reserved.