Fabrication of TiO₂/CdS Heterostructure by Soluble Solid-State Titanium-oxo-Clusters for Fast Photocatalytic Degradation of Tetracycline

Abstract

Dependent on the solubility of titanium-oxo-clusters, the molar ratios of Ti/Cd in the composite can be adjusted precisely. Herein, a soluble solid-state titanium-oxo-cluster is employed as a Ti raw reactant to fabricate a TiO2/CdS photocatalyst with TiO2 nanoparticles isolated on the surface of CdS nanorods for highly efficient degradation of tetracycline (TC). The comparative experiment shows that the composite with the Ti/Cd molar ratio at 0.5 exhibits the best photocatalytic performance, which can degrade 95% TC with an initial concentration of 10 mg/L under 12 min visible-light irradiation. The excellent photocatalytic ability of the TiO2/CdS composites made of soluble titanium-oxo-clusters is superior to those of the pure CdS and TiO2, which is attributed to not only the synergic effect of TiO2/CdS heterostructure on improvement of photogenerated electron–hole pairs’ separation and lifetime but also the ideal dispersion of the isolated TiO2 nanoparticles on the surface of CdS nanorods. This work presents a facile way to achieve a highly active catalyst with controllable TiO2-involved heterostructure for photocatalytic degradation.