Fabrication of N-doped TiO2 Nanorods and Its Visible-Light Photocatalytic Activity for Resorcinol Degradation in Wastewater

Abstract

This work was focused on the synthesis of N-doped TiO2 nanorods as photocatalyst and its visible-light photocatalytic activity to degrade resorcinol as phenolic pollutants in wastewater. Pure TiO2 and N-doped TiO2 NRs were synthesized using a solvothermal process. The analyses of morphology and structure of prepared photocatalysts by TEM and XRD showed that well-defined mesoporous nanorods in anatase phase were synthesized. The result of optical characterization showed that the band gap values of TiO2 and N-doped TiO2 NRs were obtained 3.04 and 2.31 eV, respectively, indicating the band gap of N-doped TiO2 NRs was greatly narrower than the pure TiO2 NRs. The results of EIS analysis showed lower resistance of carrier transfer for the doped sample. The Results of the photocatalytic study showed that the complete treatments of 100 mg/l resorcinol were obtained at 120 and 95 minutes under UV irradiation for pure TiO2 and N-doped TiO2 NRs, respectively, and complete removal was obtained at 130 and 85 minutes under visible light irradiation for pure TiO2 and N-doped TiO2 NRs, respectively. Therefore, the higher degradation rate of resorcinol on N-doped TiO2 NRs under visible light irradiation was observed which can be attributed to the narrowing band gap of doped sample and formation of an impurity energy level, avoiding the recombination between e− and h+.