Synthesis of mesoporous TiO2 nanorods via a mild template-free sonochemical route and their photocatalytic performances

A mild template-free sonochemical method has been developed to synthesize mesoporous TiO2 nanorods using industrial bulk Ti powder. The sonochemical synthesis process was carried out under normal atmospheric pressure and relative low temperature. The as prepared materials contained numerous irregular olive-like nanorods aggregates. The nanorods were 8–12 nm in width and 15–100 nm in length, with the crystalline size of 10.3 nm. A mechanism of Oxidation–Shaking off–Rolling up–Shrinkage (OSRS) has been proposed to explain the crystal growth. The photocatalytic activity of the sample was 2.8 times that of P25.