Photocatalytic degradation of bisphenol A by TiO2-reduced graphene oxide nanocomposites

TiO2-reduced graphene oxide (RGO) nanocomposites were prepared via hydrothermal synthesis. The prepared hybrid materials were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. The results indicated that P25 nanoparticles with size of 20-30 nm were dispersed on RGO sheets after the hydrothermal process. The photocatalytic activity of TiO2-RGO was evaluated by degrading bisphenol A (BPA) under UV light illumination. The photocatalytic degradation process was fitted well by the pseudo-first order reaction model. The degradation rate constants were strongly affected by the mass ratio of RGO in the hybrid materials and the optimal mass ratio of RGO to commercial TiO2 (P25) was 3.0 wt%. Under the optimal degradation conditions, the rate constant of BPA over P25-3RGO (-0.0132 min(-1)) was 2.93 times of that over P25 (-0.00451 min(-1)). The results indicated that the introduction of RGO in P25 not only can enhance the adsorption ability for BPA, but also improve the photocatalytic activity of P25 for degradation of BPA greatly.