Preparation of Visible-light Responsive Photocatalyst SxTi_(1-x)O_2

摘要

Sulfur-doped titanium dioxide powders (S_xTi_(1-x)O_2) was prepared by calcinations, that is, the hydrolysis of acidic tetra-butyl tianate using thiourea in ethanol, followed by calcinations at temperatures about 500 ℃. Based on the characterizations of XRD, BET, surface photovoltage spectroscopy (SPS), electric-field-induced surface photovoltage spectroscopy (EFISPS) and XPS, it was found that the sulfur could restrain the crystallization transformation of TiO_2 from anatase to rutile, although the calcinations temperature has attained 500°C, the crystallization still were anatase entirely. The catalysts exhibited photocatalytic activity in the visible light region owing to S-doping. The light absorption onset of S_xTi_(1-x)O_2 was shifted to the visible region at 550nm compared to 329nm of pure TiO_2. In the crystal, the S atoms occupied some of the lattice titanium atoms for form S-O bonds. Photocatalytic decomposition of benzoic acid solutions was carried out under simulated sun light, and the S_xTi_(1-x)O_2 catalyst showed higher activity than pure TiO_2.