The enhanced photocatalytic activity of Ti3+ self-doped TiO2 by a reduction method

A novel reduction method has been developed as an effective strategy to improve the photocatalytic activity and the surface photovoltage spectroscopy (SPS) response of TiO2 nanoparticles. As-prepared TiO2 nanoparticles are synthesized through hydrolysis of tetrabutyl titanate, which are subsequently reduced by NH2OH·HCl in NH3·H2O media. Abundant Ti3+ is detected on the surface of the reduced TiO2. The Ti3+ self-doped TiO2 photocatalyst exhibits enhanced photocatalytic degradation efficiency with respect to methyl orange (MO) under UV and visible light irradiation. The enhanced photocatalytic degradation efficiency of Ti3+ self-doped TiO2 can be attributed to the presence of active Ti3+ sites, which is favorable for the separation of photoinduced electron-hole pairs. This work provides a feasible method for the improvement of photocatalytic activity and surface photovoltage response of semiconductors.