Silver modified barium titanate as a highly efficient piezocatalyst

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.