In order to improve photocatalytic activities of the pure anatase TiO2 under UV and visible light irradiations, a novel and efficient N-doped TiO2 photocatalyst was prepared by sol-gel method. N-doped titania is prepared using the various nitrogen sources such as: triethylamine, N,N,N’,N’-tetramethylethane-1,2-diamine, ethyldiamine, 1,2-phenylenediamine, propanolamine, and...