Ag Nanoparticles Decorated TiO₂ Thin Films with Enhanced Photocatalytic Activity

Abstract

A highly photocatalytic Ag/TiO 2 thin film is prepared by the photocatalytic deposition of Ag nanoparticles (NPs) on reactive sputtered columnar TiO 2 structures. By altering the ultra‐violet (UV) exposure time, the authors control the morphology and surface coverage of deposited Ag NPs. While a surface coverage of 1–4% (by Ag NPs) leads to a significant increase in the photocatalytic activity, depositing more Ag NPs yield a decrease in the photocatalytic performance (lower than that of bare TiO 2 ). This may arise due to the blocking of UV light incoming to the TiO 2 by the formation continuous network of Ag clusters on the surface. Such highly interconnected Ag clusters might also trigger the recombination of electron‐hole pairs. After five consecutive photocatalysis tests, the Ag (1 min)/TiO 2 thin film remains intact.