Enhanced photocatalytic activity of three-dimensional TiO2/reduced graphene oxide aerogel by efficient interfacial charge transfer

TiO2 is one of the most widely used photocatalytic semiconductors. However, the rapid recombination of photogenerated electron-hole pairs severely weakens its photocatalytic activity. Herein, a three-dimensional TiO2/ reduced graphene oxide (TiO2-rGO) aerogel with enhanced interfacial charge transfer was synthesized by a facile hydrothermal method, and its photocatalytic degradation of Methylene Blue (MB) and Reactive Red 24 (RR24) dyes was investigated. The photocatalytic results showed that TiO2-rGO aerogel possesses excellent photocatalytic activity, and its photocatalytic degradation rate towards dyes is more than 3.8 times that of pure TiO2 and more than 2.7 times that of TiO2-GO aerogel. Characterization results indicated that the significantly enhanced photocatalytic activity of TiO2-rGO aerogel could be attributed to the enhanced pi-conjugated structure of rGO, which can effectively increase interfacial charge transfer and inhibit electron-hole pairs recombination. The mechanism suggested that center dot OH and center dot O-2(-) are the active species in the photocatalytic degradation process. Our findings can provide an important reference for the preparation of high-performance TiO2-based photocatalysts.