Photoelectrochemical and photocatalytic properties of N + S co-doped TiO2 nanotube array films under visible light irradiation

摘要

In this paper, we report on the co-doping nitrogen and sulfur has beenachieved in the TiO2 nanotube array films by treatment with thiourea andcalcination under vacuum at 500 {\deg}C for 3 h. The samples were characterizedby scanning electron microscopy, X-ray diffraction (XRD), X-ray photoelectronspectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy.XPS spectra revealed that N might coexist in the forms of NTiO and NOTi, S wasincorporated into the lattice of TiO2 through substituting oxygen atoms in theN + S co-doped TiO2 nanotube array films. XRD patterns indicated that improvedcrystallinity was obtained for N + S co-doped TiO2 nanotube arrays as comparedto that of undoped TiO2 nanotube arrays. In photoelectrochemical measurements,the photocurrent of N + S co-doped TiO2 nanotube array films was greatlyenhanced compared to that of undoped samples under visible light irradiation.And the photocatalytic activities of the samples were evaluated on the removalof methylene blue under visible light irradiation. The N + S co-doped TiO2nanotube array films showed a better photocatalytic activity than the undopedsample due to the N, S doping. Keywords: Nanostructures; Oxide; Thin films; Electrochemical properties