Investigation on photocatalytic properties of RE-Doped titanium dioxide nanoparticles through sol - gel technique

The photocatalytic activity was studied under UV light using AC-Cd/TiO 2 prepared via precipitation method and characterized by powder X-ray diffraction (XRD) , high resolution scanning electron micrographs (HR-SEM) with energy dispersive X-ray analysis (EDX), photoluminescence (PL) and Fourier transform Raman analysis (FT-RAMAN). The enhanced photo catalytic activity of the AC-Cd/TiO 2 is demonstrated through photodegradation of methylene blue under UV light radiation at 365 nm. The mechanism of photocatalytic effect of AC-Cd/TiO 2 Nano composite material has been discussed Further its antibacterial activity against two gram positive and two gram negative bacterial strain is studied.

The photocatalytic activity was studied under UV light using AC-Cd/TiO 2 prepared via precipitation method and characterized by powder X-ray diffraction (XRD) , high resolution scanning electron micrographs (HR-SEM) with energy dispersive X-ray analysis (EDX), photoluminescence (PL) and Fourier transform Raman analysis (FT-RAMAN). The enhanced photo catalytic activity of the AC-Cd/TiO 2 is demonstrated through photodegradation of methylene blue under UV light radiation at 365 nm. The mechanism of photocatalytic effect of AC-Cd/TiO 2 nanocomposite material has been discussed Further its antibacterial activity against two gram positive and two gram negative bacterial strain is studied.

Visible light-sensitive carbon doped titanium dioxide nanoparticles (C-TiO2) were prepared by a sol-gel method. The carbon dopant was obtained from glucose. The dopant level incorporated into the TiO2 lattice structure was varied by using different concentrations of the carbon source solution. The nanoparticles were characterized by X-ray diffraction (XRD), BET Surface area, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Scanning X-ray photoelectron spectroscopy (SXPS) and Diffuse reflectance spectroscopy (DRS). The presence of carbon in the TiO2 lattice was determined by SXPS. The DRS results revealed that carbon doping reduced the band gap of TiO2. Doping was also found to cause a reduction in the particle size of the TiO2 nanoparticles and enhance anatase to rutile phase transformation. The photocatalytic activities of the prepared samples were evaluated by the photocatalytic degradation of methyl orange. The carbon doped TiO2 showed a higher photocatalytic activity than degussa P25 and undoped TiO2.

Rare earth ions (Y3+,La3+,Nd3+) doped TiO2 catalysts were prepared by the sol-gel method, and characterized by X-ray diffraction (XRD) and UV-vis diffuse reflectance spectroscopy (DRS). The photocatalytic activities of doped TiO2 were evaluated with methylene blue degradation under UV light. The anatase to rutile phase transformation of doped TiO2 was significantly inhibited by rare earth ions doping, and the inhibitory effect was related to ion radius with a sequence of La3+> Y3+> Nd3+. The doped rare earth ions were in form of rare earth oxides, which adsorbed on TiO2 surface to efficiently separate charge carriers. Rare earth ion doping in TiO2 can extend light absorption properties to the visible region, which indicates the reduced band gap position of doped TiO2. The content of doped rare earth ions was an important factor affecting photocatalytic activity. The optimum amount of rare earth doping is 0.1∼0.15wt%, at which the photo-reactivities of doped TiO2 were about 20% higher than that of pure TiO2.

TmVO4 precursor gel was prepared by sol-gel method using thulium oxide, nitric acid, ammonium metavanadate and citric acid as main raw materials. Then the xerogel was calcined at 600–800 °C in muffle furnace to prepare TmVO4. The prepared samples were characterized by thermogravimetric differential scanning analysis (TG-DSC), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy(DRS) and Fourier transform infrared spectroscopy(FT-IR). The visible-light photocatalytic activity of TmVO4 was studied by using methylene blue solution as simulated wastewater. The result shows that TmVO4 can be obtained by calcination at 700 °C. The average grain size is about 80 nm and the bandgap is 2.16 eV. Under visible-light conditions, the degradation rate of methylene blue can reach more than 90% when methylene blue solution of 10 mg/L was illuminated 60 min in the presence of nanoparticulate TmVO4. The nanoparticulate TmVO4 has excellent photocatalytic degradation activity for methylene blue. Nanoparticulate TmVO4 prepared by sol-gel method has broad application prospects in photocatalytic degradation of organic pollutants.