Effect of Configuration on the Photocatalytic Activity of AgNPs-TiO 2 System

This paper studies the effect of the configuration of silver nanoparticles (AgNPs)-TiO2 on the visible-light-driven photocatalytic activity (PA). Three configurations were fabricated by vacuum thermal deposition: configuration I, AgNPs deposited on the surface of TiO2 thin films; configuration II, AgNPs deposited on a glass and covered by TiO2 thin films; and configuration III, AgNPs deposited on the surface of TiO2 thin films and covered by TiO2. The PAs of the three configurations were studied and compared. Our study indicates that configuration II is the most cost-efficient one, while configuration III could obtain the highest visible light-induced PA. The maximum of PA could be achieved when the top layer of TiO2 is less than 2 nm. The mechanisms were discussed from three aspects, the influence of TiO2 thickness on the localized surface plasma resonance (LSPR) of AgNPs, the separation, and the transportation of hot carriers. By this study, the most effective way to make use of the PA of TiO2-AgNPs was scientifically searched out.