TiO2-based photocatalysis technology was developed and applied to photodegradation of organic contaminants by utilizing solar energy effectively.Pure and doped or co-doped TiO2 catalysts with various amounts of lanthanum and carbon were obtained by a modified sol-gel process

in which tetrabutyl titanate was used as precursor and lanthanum nitrate

tetrabutylammonium hydroxide as ion donors.The as-prepared photocatalysts were found to be of anatase phase

higher specific area

and visible response by means of XRD

BET and UV-vis spectra analysis.The co-doped TiO2 catalysts showed higher photocatalytic activity in degradation of rhodamine B

methyl orange and 4-chlorphenol under Xe lamp

sunlight or daylight irradiation than that of pure and single doped ones.Photodegradation experiments showed that the co-doped catalyst with 0.5% (molar ratio) lanthanum calcinated at 500℃ was of the highest catalytic efficiency under visible irradiation.The higher visible light photocatalytic activity of co-doped TiO2 was attributed to the doped carbon that lowered the ban