Enhanced photocatalytic activity of TiO2 nanoparticles using WS2/g-C3N4 hybrid as co-catalyst
(School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China)
Abstract: TiO2/WS2/g-C3N4 composite photocatalysts were synthesized by a liquid-exfoliation-solvothermal method. In this process, the WS2/g-C3N4 nano-sheets were prepared by liquid-exfoliation method from the bulk WS2 and C3N4 in the alcohol system, and then the TiO2 nanoparticles (NPs) grew on the WS2/g-C3N4 nano-sheets by in-situ synthesized technique. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic degradation of methyl orange (MO). The results showed that the as-prepared samples exhibited higher photocatalytic activities as compared to the pure TiO2, g-C3N4 and TiO2/g-C3N4 composite. The enhanced photocatalytic activities of TiO2/WS2/g-C3N4 photocatalysts could be attributed to the synergistic effect of heterostructure between TiO2 NPs and WS2/g-C3N4 nano-sheets, which could efficiently improve the separation of photogenerated electron/hole pairs and utilization efficiency of photons. The quenching tests of radicals indicated that had crucial effect on degradation of MO, which demonstrated that was the main active radical in photocatalytic reaction process.
Key words: g-C3N4; TiO2; WS2; photocatalysis; liquid-exfoliation; solvothermal method