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With an attempt to investigate the effect of gold impurity and tungsten oxide on the recombination and separation of electron hole pairs, and disclose the effect of surface state on the photo catalytic activity of TiO 2, an innovative photo catalyst 3%WO 3/0.5%Au 3+ /TiO 2 was prepared by means of sol gel method. The photo oxidation efficiency of photo catalyst was evaluated by conducting a set of experiments to photo degrade methylene blue (MB) in aqueous solution. The surface state properties were examined by means of surface photovoltage spectra (SPS) and electron field induced SPS (EFISPS). The experiments demonstrate that the strongest peak is attributed to electron excited from valence band to conduction band and the second strongest peak is attributed to electron excited from valence band to oxygen molecular for all samples. Electron is trapped by O 2 absorbed on the surface of TiO 2. And the surface state of O - 2 forms. For (1%, 3%)Au 3+ /TiO 2 sample, two new peaks that significantly present at 414?nm and 400?nm respectively should be attributable to gold impurity energy level. And for tungsten oxides doping samples, 4 peaks that significantly present in the region of 500～800?nm should be attributable to tungsten impurity energy level. The intensity of EFISPS decreases with increasing the content of gold ion or tungsten oxide when its content is no more than their optimal dosage. However, when the content of gold ion or tungsten oxide is more than their optimal dosage, impurity energy level becomes recombination center from separation center and the intensity of all peaks increases for them.
With an attempt to investigate the effect of gold impurity and tungsten oxide on the recombination and separation of electron hole pairs, and disclose the effect of surface state on the photo catalytic activity of TiO 2, an innovative photo catalyst 3% WO 3 / 0.5% Au 3+ / TiO 2 was prepared by means of sol gel method. The photo oxidation efficiency of photo catalyst was evaluated by conducting a set of experiments to photo degrade methylene blue (MB) in aqueous solution. The surface state properties were examined by means of surfaces photovoltage spectra (SPS) and electron field induced SPS (EFISPS). The experiments demonstrate that the strongest peak is attributed to electron excited from valence band to conduction band and the second strongest peak is attributed to electron excited from valence band to oxygen molecular For all samples. Electron is trapped by O 2 absorbed on the surface of TiO 2. And the surface state of O - 2 forms. For (1%, 3%) Au 3+ / TiO 2 sample, Two new peaks that significantly present at 414 nm and 400 nm should be attributable to the gold impurity energy level. And for tungsten oxide doping samples, 4 peaks that significantly present in the region of 500-800 nm should be attributable to tungsten The energy of EFISPS decreases with increasing the content of gold ion or tungsten oxide when its content is no more than their optimal dosage. However, when the content of gold ion or tungsten oxide is more than their optimal dosage, impurity energy level becomes recombination center from separation center and the intensity of all peaks increases for them.