Investigation on g-C3N4/rGO/TiO2 nanocomposite with enhanced photocatalytic degradation performance

Three phase nanocomposites g-C3N4/rGO/TiO2 were synthesized successfully under hydrothermal reaction conditions using g-C3N4 nanosheets as matrix, as well as TiO2 sol and graphene oxide as the precursors of nano-size anatase and reduced graphene oxide (rGO), respectively. The photocatalytic performance of samples was investigated by degrading Rhodamine B (RhB) solution under sunlight irradiation with a xenon lamp. The results show that g-C3N4/rGO/TiO2 three-phase composite nanomaterial was successfully prepared. g-C3N4/rGO/TiO2 exhibited a satisfactory photocatalytic activity and cycle stability when the mass ratio of g-C3N4 nanosheets (0.6 g) to nano-TiO2 (0.2 g) was 3:1, the mass of GO was 0.002 g, the hydrothermal temperature and time were 160 °C and 6 h, respectively. When photocatalysis for 60 min, the degradation rate of RhB solution (100 mL, 10 mg/L) by g-C3N4/rGO/TiO2 (100 mg) reached 99.63%. Main reasons for these results lie in the significantly improved separation efficiency of photogenerated electron-hole pairs due to the construction of g-C3N4/TiO2 heterojunction, the enhanced optical absorption and the increased specific surface area.