Preparation of visible light responsive N doped TiO_2 via a reduction-nitridation procedure by nonthermal plasma treatment

摘要

A visible light responsive N-doped TiO_2 was prepared via a reduction-nitridation procedure by nonthermal plasma treatment. X-ray diffraction, N_2 adsorption, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared TiO_2 samples. The plasma treatment did not change the phase composition and particle sizes of TiO_2 samples, but extended its absorption edges to the visible light region. The photocatalytic activities were tested in the degradation of an aqueous solution of a reactive dyestuff, methylene blue, under visible light. The photocatalytic activities of TiO_2 prepared by reduction-nitridation procedure were much higher than that of samples prepared by simple nitridation treatment. The enhanced activity was ascribed to the substitutional Ndoping and appropriate concentration of oxygen vacancies. TOHN10 prepared by reduction-nitridation procedure exhibited excellent photocatalytic stability. A possible mechanism for the photocatalysis was proposed.