Photo-catalyst composed of nano-sized TiO2 doped with Fe3+ was prepared by microemulsion method using cetyltrimethylammonium bromide as surfactant,n-butanol as co-surfactant and cyclohexane as oil phase.The particle of TiO2 and the phase structure were identified by X-ray diffraction.Photo-catalytic performance of the catalyst was examined by the photo-catalytic degradation of methyl orange solution.Laboratory results showed that under condition of pH=2,the degradation can achieve 100%.The doping of Fe3+ wi...