Study On The Construction And Properties Of PANI-based Composite Photocatalytic System

Photocata lytic oxidation technology is a new technology of modern environmental pollution control.As a traditional material,TiO₂ has many advantages,such as non-toxic,low cost,stable performance and high catalytic activity.It has a broad application prospect in the treatment of environment pollutants.It is the focus and hotspot of the current research to enhance the photocatalytic activity of TiO₂ photocatalyst under visible light and to solve its problem that it is difficult to separate and recycle in liquid system.In this paper,nano-TiO₂ photocatalyst was prepared by sol-gel method,hollow glass beads（HGM）as the carrier and nano-CoFe2O4 as the magnetic core respectively,nano-TiO₂ was modified by PANI at the same time.Two different kinds of PANI-based composite photocatalysts were prepared,that is PANI-TiO₂-HGM and CoFe2O4-PANI-TiO₂.The XRD,SEM,EDX,Raman,FT-IR,UV-Vis,BET and VSM technology were used to characterize the photocatalyst.Under the irradiation of visible light,indigo carmine solution was selected as the target degradation product.In-depth study of photocatalytic activity,the the optimum dosing,the recycling stability and the main active component in the photocatalytic system.The results of photocatalytic degradation of indigo carmine solution were obtained:while the optimum dose of PANI-TiO₂-HGM,CoFe2O4-PANI-TiO₂ were 2.0 g/L,1.0 g/L,the photocatalytic were 97.0%,99.0%;after five times of photocatalytic cycling,the degradation rate decreased by only 8.9%,6.2%,it can still maintain a high photocatalytic activity and better cycle stability;we also discuss the main active components in the photocatalytic system by adding the trapping agent,the results show that photogenerated holes play an important role in the photodegradation system.