Facile fabrication of SnO2/TiO2 nanotube arrays for efficient degradation of pollutants

Abstract

Herein, an efficient Z-scheme SnO2/TiO2 nanotube arrays (NTAs) was synthesized through a facile solvothermal method. The investigation indicates that SnO2 can improve the photoelectrocatalytic (PEC) activity of TiO2 NTAs, the photocurrent density of 0.07-SnO2/TiO2 NTAs can reach 0.94 mA cm−2, which is 4.48 times higher than that of TiO2 NTAs. The PEC degradation efficiency of MB and RhB (5 mg·L−1) is 94.71% and 80.58% over 0.07-SnO2/TiO2 NTAs after 90 min under 300 W Xe lamp irradiation, and the film-shaped 0.07-SnO2/TiO2 NTAs maintains a stable PEC performance during four times of recycling without a complex separation process. Based on the energy band structures analysis and the radical trapping experiments, the boosted PEC activity is benefited from a Z-scheme charge transfer route between SnO2 and TiO2 NTAs, which can inhibit the charge recombination and maintain the strong redox capacity of electrons and holes. This work provides a simple way to construct film-shaped TiO2 based heterojunction in PEC technology for environmental pollution remediation.