2-Propanol photodegradation over nitrogen-doped NaNbO3 powders under visible-light irradiation

Nitrogen-doped perovskite-type materials, yellowish NaNbO3-xNx powders, had been developed as visible-light-sensitive photocatalysts for decomposition of gaseous 2-propanol. The NaNbO3-xNx samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis) light diffuse reflectance spectroscopy, Brunauer-Emmett-Teller (BET) measurement, and scanning electron microscopy (SEM). The UV-vis spectra confirmed that the spectral response of the NaNbO3 powders could be tuned to visible-light region by nitrogen doping technique. The photocatalytic activities of NaNbO3-xNx samples were evaluated by decomposing gaseous 2-propanol into acetone and CO2 under visible-light irradiation (400 mm < lambda < 520 nm). The NaNbO3-xNx sample annealed at 833 K showed the highest visible-light photocatalytic activity among all the nitrogen-doped samples. The relationship between nitrogen doping amount and photocatalytic activity of NaNbO3-xNx samples was also investigated and discussed. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.