A F-ion assisted preparation route to improve the photodegradation performance of a TiO2@rGO system-how to efficiently utilize the photogenerated electrons in the target organic pollutants

Abstract

A comparison of the work function of reduced graphene oxide (rGO) and the conduction band position of TiO₂ reveals that the density of TiO₂ particles grown on rGO could affect the photodegradation efficiency of a TiO₂@rGO heterojunction. Herein, with the introduction of F-ions into the preparation route, F-doped shaped TiO₂ nanocrystals are densely and uniformly decorated on rGO sheets via the ice bath hydrolyzation method. Thus, more dye molecules are adsorbed on the surface of TiO₂ and the photogenerated electrons in the excited dye molecules could be efficiently utilized to improve the overall photodegradation efficiency. The as-prepared F-doped TiO₂@rGO heterojunction showed extremely high photocatalytic efficiency under UV-vis light irradiation compared with that of the commercial P25 and the mixture of F-TiO₂ and rGO. It is proved that the ice bath hydrolyzation preparation route is crucial to improve the photodegradation efficiency of the final product since the pure TiO₂@rGO heterojunction is also much more efficient than the mixture of F-TiO₂ and rGO. The present work provides new insights into efficiently utilizing the photogenerated electrons in the target organic pollutants.