Hydrogen evolution from aqueous methanol solution on mesoporous titania prepared by a process combining evaporation induced self-assembly and spray pyrolysis

Mesoporous TiO2 powders were prepared in 1 min from an aqueous mixture of chelated complex titanium precursor and tri-block copolymer by using a process combining evaporation induced self-assembly (EISA) and spray pyrolysis. Photocatalytic activity was evaluated by measuring the rate of hydrogen evolution from methanol solution. The prepared powders were mainly anatase phase and had worm-like pores. Crystallite size was in the range from 7.8 to 18.6 nm in diameter. The mesoporous TiO2 powders calcined at 823 K had surface area of 144 m2 g−1 and high pore volume of 0.33 cm3 g−1. Pore size distribution was also narrow. In addition, it had high light absorption intensity below 350 nm. The rate of hydrogen evolution was by a factor of six higher than the rate measured with commercial nano-sized TiO2 powder (Degussa P-25). Unique structural and optical properties, which were mainly originated from our new combined process of EISA and spray pyrolysis, contributed to the enhanced rate of hydrogen evolution.