Z-scheme TiO@TiC/CdZnS nanocomposites with efficient photocatalytic performance via one-step hydrothermal route.

Photocatalytic degradation of pollutants has been proved to be an effective strategy for wastewater treatment. Herein, TiO nanoparticles were synthesized on a TiC matrix by in situ growth, forming Z-scheme TiO@TiC/CdZnS (TO/CZS) multilevel structured nanocomposites via one-step hydrothermal route. The effects of hydrothermal temperature and CdZnS content on microstructure and properties of composites were assessed. TO/CZS nanocomposites were probed into phase composition, morphological and optical properties with x-ray diffractometer, infrared radiation, scanning electron microscope and UV-vis reflective spectra. Following the hydrothermal reaction at 160 °C for 12 h, TiO nanoparticles of 30 nm in diameter were generated in situ on TiC lamina and CdZnS particles were evenly distributed on the TiC matrix. The photocatalytic activity of TO/CZS composites were evaluated, which found that degradation rate constant (k = 0.028 min) of TO/CZS-40 on Rhodamine B was 5.19 times that of pure TiO and 4.48 times that of CdZnS. Through anchoring TiC as an electron transition mediator and combination with TiO and CdZnS, the new Z-scheme between TiO oxidized by TiC and CdZnS establishes a multilevel structure of separating electron-hole pairs. This work demonstrates a valid way to control electrons and hole transfer directions efficiently through designing multilevel semiconductor structural designs.