Electrical and optical properties of nanocrystalline-Cu-doped TiO2 prepared by precipitation method

Abstract

Electrical and optical properties of copper doped onto nanocrystalline of titanium dioxide nanoparticles (TiO2 NPs) prepared by precipitation method were investigated. NaOH of 1 M, copper nitrate trihydrate and powder
of TiO 2 NPs were used as starting materials by varying ratio of Cu- doped TiO2 from 2 to 30 %wt. The product of precipitation process was dried at a temperature of 120 °C for 6 h and used temperature of 300 °C for 0.5 h in the
calcination process. After then, the UV-Vis spectroscope was used for analyzing the electrical and optical properties of the powder. It was found that the absorbent analysis showed the wavelength in the range of 302 - 309 nm, the
absorbance at 2.05 - 3.88 a.u., and 3.88 at the optimum doping of 15 %wt. The energy band gab is the indirect band gap. It was found that the energy band gap decreased with increasing the doping percent of Cu. However,
the doping Cu onto TiO2 NPs exhibits the different wavelengths and energy band gaps from pure TiO2 NPs. The wavelength of 314 nm and the energy band gap of 3.33 eV were occurred for an only TiO2 NPs powder whereas
the only Cu powder (100 %wt. Cu-doped TiO2) possess wavelength and energy band gap of 349 nm and 2.45 eV, respectively. Therefore, the doped Cu has affected the electrical and optical properties of TiO2 NPs.