Surface defect and rational design of TiO2−x nanobelts/ g-C3N4 nanosheets/ CdS quantum dots hierarchical structure for enhanced visible-light-driven photocatalysis

TiO 2-x /g-C 3 N 4 /CdS ternary heterojunctions are fabricated through thermal polymerization-chemical bath deposition combined with in-situ solid-state chemical reduction approach. The prepared materials are characterized by X-ray diffraction, Fourier transform infrared spectra , scanning electron microscopy, transmission electron microscopy , nitrogen adsorption-desorption, and X-ray photoelectron spectroscopy. The results show that the ternary heterojunctions are formed successfully and CdS quantum dots (QDs) and TiO 2 are anchored on surface of g-C 3 N 4 nanosheets simultaneously. The visible-light-driven photocatalytic degradation ratio of Bisphenol A and hydrogen production rate are up to 95% and ∼254.8 μmol h −1 , respectively, which are several times higher than that of pristine TiO 2 . The excellent visible-light-driven photocatalytic activity can be ascribed to the synergistic effect of TiO 2−x , g-C 3 N 4 and CdS QDs which extend the photoresponse to visible light region and favor the spatial separation of photogenerated charge carriers.