Investigation of adding TiO2 nanoparticles on the electrical conductivity of RGO_ZnO nanocomposite

This present research was related to electrical conductivity of RGO-ZnO-TiO2 nanocomposite in comparison RGO-ZnO nanocomposite . In order to carry out this research, at first graphene oxide was synthesized by using modified Hummer method and reduction of graphene oxide (reduced graphene oxide(RGO), was done by UV light and temperature. TiO2 and ZnO nanoparticles were synthesized by sol-gel method.XRD,FTIR and DRSUV were used to investigate these nanoparticles.
For sample preparation ,dip coating method was used and all particles were coated on the surface of FTO respectively. for investigation of adding TiO2 nanoparticles on the electrical conductivity and amount of band gap of RGO-ZnO nanocomposite, electrochemical impedance spectroscopy and talc plot were used .
The results of comparison between these 2 samples showed that adding TiO2 nanoparticle to RGO-ZnO nanocomposite reduced band gap from 3.22 to 3.11 and increase resistance from 2.8*104Ω to 5.76*104Ω . with study of level energy of RGO, ZnO and TiO2 nanoparticles ,the reason of increasing resistance related to higher ZnO energy level in comparison to TiO2 energy level and electron Inability to overcome of this level energy in the absence of UV light .with putting this sample under UV light could be reduced this resistance.