TiO2 treated in hydrogen atmosphere showed enhanced photocatalytic activity in degrading the sulfosalicylic acid （SSal）.The results of the electrochemical impedance spectroscopy （EIS） investigation showed that the diameters of the capacitive arcs for the H-TiO2 were much smaller than those of bare TiO2 and thermally treated TiO2 in air,indicating that the charge transfer of the H-TiO2 occurs more rapidly,thus inviting a higher photocatalytic activity.When an external bias was applied on the H-TiO2,the arc of the EIS Nyquist plot decreased obviously than without the bias,suggesting more efficient separation of the photo-generated carriers.
A three dimensional electro assisted photocatalytic system was constituted with granular TiO 2 as the photocatalyst. The photocatalytic efficiency of phenol degradation was observed to be 10% and 33.6% , respectively, for common water electrolysis and photocatalysis, while it is increased to 82.8% for the combination of them i.e., the electro assisted photocatalytic system. According to the experimental results, both water electrolysis and anode bias were considered to be responsible for the electro synergism, which may effectively provide active oxygen source and prevent further recombination of photo generated charges.
