Structure And Catalytic Property With Visible Light Of Fe³⁺(Gd³⁺)/TiO₂Composite Nanoparticles By Microwave Radiation Technology

Nano-TiO2crystalline has been paid much attention with its properties, such as low-cost, easy-get, environment-friendly, chemical stability and so on. However, TiO2is a semiconductor with wide band gap, which only be excited by ultraviolet light (λ<387.5nm) that restrict its application. Therefore, the research on modifying nano-TiO2with visible light response activity and high efficiency is significant.In this paper, TiO2nanoparticals doped with Fe3+(or Gd3+) were synthesized using microwave radiation as heat source. Some means, such as TEM, XRD, TG-DTA and UV-Vis were used to character these composite nanoparticles.The microwave hydrothermal method and impregnation process were used to synthesize TiO2composite nanoparticles doped with various amount of Fe3+. The UV-Vis Diffuse Reflectance Spectra showed that adsorption peak of Fe3+/TiO2nanoparticles shifted to visible range. The composite nanoparticles with lessen sized and higher dispersity were seen in TEM pictures. The XRD results showed that when the doping amount of Fe3+is10%, the separate diffraction peak of Fe2O3phase was observed. The Fe3+/TiO2composite materials synthesized with different methods present variant photocatalytic activity. The Fe3+/TiO2nanopaticles through dopping anatase TiO2in Fe(NO3)3solution showed highest activity, which degradate nearly100%Methyl Orange in100minutes.The Gd3+/Ti02composite nanoparticles were prepared through three different processes. The anatase TiO2doped with Gd3+could be obtained by microwave hydrothermal process without heat treatment, by which the degradation efficiency of Methyl Orange was70%in2hours. The composite nanoparticles could also be synthesized by impregnating TiO2particles in anatase (or anorphism) in the Gd(NO3)3solution, which present different photocatalytic properties toward Methyl Orange inradiated by visible light. Generally, the microvave souce is helpful for improving the dispersity, decreasing particle size. Homogeneous precipitation method was also used to synthesize Gd3+/TiO2composite nanoparticles. When doping amount of Gd3+is1%, the composite materials showed a high degree of crystallization and the photocatalytic activity than that of pure TiO2nanoparticles.