Effect of UV irradiation on synthesis of Ag/amorphous TiO2 composites with photocatalytic hydrogen production

Abstract

TiO2 has the characteristics of low cost and good optical stability, but its light absorption range is narrow and its electrons are easy to combine with. The addition of metal nanoparticles can help to improve its charge transfer rate and improve its catalytic performance. In the paper, amorphous TiO2 pore structure was obtained using PVP as a template and then Ag was deposited on the surface of TiO2 through a simple ultraviolet light illumination. With increase of irradiation time, the distribution and deposition state of Ag particles were different. Through the electrochemical test, it was found that the deposition of Ag particles in a-TiO2 decreased impedance and improved the hole–electron pairs’ separation efficiency and carrier concentration. After 15-h irradiation, Ag/a-TiO2 composite can form a uniform Schottky barrier and its photocatalytic hydrogen production effect was the best. The highest hydrogen production rate in 15 h of UV light reached 400.3 μmol g−1 h−1. Finally, the electron transfer mechanism of Ag/a-TiO2 was explained.