Enhanced photocatalytic performance of TiO 2 nanotube based heterojunction photocatalyst via the coupling of graphene and FTO

The TiO 2 nanotube (TONT) based heterojunction photocatalyst was developed via the coupling of reduced graphene oxide (rGO) and SnO 2 :F film (FTO). Based on the characterization of Raman analysis, XRD, SEM, TEM, XPS and ESR, the crystal phase, morphology, heterojunction interfacial interaction and the photoinduced electron chemical environment of the samples are studied. In the photodegradation of methylene blue (MB) solution under UV irradiation, the rGO-TONT/FTO heterojunction photocatalyst exhibits the improved photocatalytic reaction rate, 3 times greater than that of pure TONT. The enhanced photocatalytic mechanism was discussed by PL. The effectively separate charge in heterojunction structure of rGO-TONT/FTO is responsible for the enhanced photocatalytic activity. Wherein, the abundant oxygen vacancies at TiO 2 surface and the chemically bonded interface in rGO-TONT heterojunction also contributes to the interfacial electron transfer. Besides, the introduction of rGO enhanced its optical absorption capacity.