Formation of Ag nanoparticles on water-soluble anatase TiO2 clusters and the activation of photocatalysis

Ag nanoparticles were directly deposited on anatase TiO2 clusters via a two-step route, which included a 60Co γ-ray irradiation method after acidic peptization of amorphous TiO2. The as-prepared TiO2 clusters could act as effective stabilizers to immobilize Ag nanoparticles reduced in the process of γ-radiolysis. The composite consisted of TiO2 particles with about 5nm and Ag particles with less than 2nm in diameter, and it was highly dispersed in aqueous solution and thermodynamically stable. After calcining Ag/TiO2 composites in flowing N2 gas, a largely enhanced photocatalytic activity was verified by photodegradation of methylene blue (MB).