Preparation And Photocatalytic Prorerties Of Mesoporous RGO/TiO₂ Composites

Photocatalytic oxidation technology of TiO₂ is a kind of synthetic dye pollutants degradation method,which possesses the advantages of nontoxic,low-priced and high catalytic efficency.Mesoporous TiO₂ can provide greater specific surface area and more developed porous structure,which could effectively improve the photocatalytic activity.But there still exists some inherent defects of mesporous TiO₂,such as low quantum efficency and easily aggregation,etc,which obstructs its industrial application.Due to the special two-dimensional plane structure,graphene has great specific surface area and excellent electrical conductivity,which lays a foundation for its application in the photocatalytic field.Nowadays lots of research outcome about graphene/ TiO₂ and mesoporous TiO₂ have been published,but there are few reports about mesoporous graphene/TiO₂.Therefore,this study first prepared a series of mesoporous reduced graphene oxide/TiO₂?PVP?composites?RGO/TiO₂?PVP??with different contents of reduced graphene oxide?RGO?by an template assisted sol-gel method using polyvinylpyrrolidone?PVP?as template to solve the issues of mesoporous TiO₂.The effects of RGO on the lifetime of photogenerated electron-hole pairs,adsorption capacity and photocatalytic activity of mesoporous TiO₂?PVP?were investigated,respectively.Then different adoption amounts of the triblock copolymer PEO₂0PPO70PEO₂0?P123?was ued as template to prepare mesoporous reduced graphene oxide/TiO₂?P123?composites?RGO/TiO₂?P123??to explore the effect of P123 on the specific surface area,pore size distribution,adsorption capacity and photocatalytic activity of RGO/TiO₂ composites.The study results indicated that in addation to inhibit the hydrolysis of tetrabutyl titanate?TBT?,citric acid?CA?could also utilize the complexing action to obtain mesoporous RGO/TiO₂?PVP?and mesoporous RGO/TiO₂?P123?with evenly distributed TiO₂.PVP and P123 are oriented adsorption with TBT by weak coordination bond,so after high temperature decomposition could form mesoporous structure in RGO/TiO₂ composites.The introduction of RGO effectively inhibits the recombination ofphotoinduced electron-hole pairs,prolongs the life of photoinduced carrier and enhances the capacity of light absorption,as well as prompts the light of the photocatalyst response range extended to visible light area.The adsorption capacity and photocatalytic activity of RGO/TiO₂?PVP?with different contents of RGO are all superior to TiO₂?PVP?,and the 7wt%RGO/TiO₂?PVP?shows the best adsorption capacity and the 5wt%RGO/TiO₂?PVP?possesses the best photocatalytic activity.P123 effectively enhances the adsorption capacity and photocatalytic activity of RGO/TiO₂,and the RGO/TiO₂?3wt%P123?reveals the highest adsorption capacity and photocatalytic activity.After repeatedly recovery test,5wt%RGO/TiO₂?PVP?and RGO/TiO₂?3wt%P123?still retain high photocatalytic degradation efficinecy,which have the ideal practical industry application prospect.