Bimetallic Sulfide MCdS Modified with TiO2 Nanoneedle Cocatalyst for Enhancing Photocatalytic H2‐evolution

Abstract

AbstractMetal ion doping and composite materials preparation are the effective means to improve the activity of CdS photocatalysts. In this work, TiO2/MCdS (M=Zn, Ni) were synthetized by two steps hydrothermal method. The morphology, elemental composition and optical properties of TiO2/MCdS photocatalysts were characterized via XRD, SEM, TEM, XPS and UV‐Vis. Interestingly, TiO2 nanoneedles were able to grow inside ZnCdS particles, which caused a strong interaction between TiO2 and ZnCdS was formed. However, TiO2 nanoneedle and NiCdS were not closely combined. As a result, the TiO2/ZnCdS (581.8 μmol ⋅ g−1 ⋅ h−1) possessed the optimal H2 production rate and showed a 1.5‐fold improvement compared to TiO2/NiCdS. This improvement of photocatalytic activity was mainly attributed to the effective separation of photogenerated electron hole pairs and the synergistic catalysis of water decomposition into hydrogen by TiO2 nanneedle‐assisted catalyst. Thus, metal ion doping and TiO2 nanoneedle as co‐catalyst could improve the photocatalytic H2 production activity of CdS more effectively.