Silver modified barium titanate as a highly efficient piezocatalyst

Abstract

As a new catalytic effect, piezocatalysis has attracted much attention due to its ability to degrade organic pollutants under mechanical vibration. However, improving the efficiency of piezocatalysis still remains a challenge. Here, we report an efficient route to enhance the piezocatalytic performance of BaTiO₃ by surface modification with Ag nanoparticles (NPs). The Ag NPs were deposited by a facile in situ photo-reduction method. The piezocatalytic efficiency of the as-prepared samples was investigated by monitoring the degradation of methyl orange (MO) under ultrasonic vibration in the dark. The results indicate that the Ag loaded BaTiO₃ particles show greatly enhanced piezocatalytic activity for degradation of MO molecules. A suitable amount of Ag deposition gives the highest piezocatalytic activity, while a higher Ag loading leads to reduced piezocatalytic activity. The degradation of MO and the possible by-products as well as the active radical species generated in the piezocatalytic system were investigated systematically. Based on the experimental results, a mechanism was proposed to explain the enhancement effect of Ag NPs on the piezocatalytic performance of BaTiO₃. The strategy presented here provides a promising route towards the development of high-efficiency piezocatalysts for actual applications.