Strong tribocatalytic dye decomposition through utilizing triboelectric energy of barium strontium titanate nanoparticles

In the suspensions with the Ba0.75Sr0.25TiO3 (BST) nanoparticles with an average size ~20 nm for triboelectric energy harvesting, dye decompositions were found to occur readily in the course of a normal stirring in dark at room temperature. More importantly, the decomposition efficiency can be greatly improved through some simple modifications in stirring rods and as high as 99.0% Rhodamine B can be decomposed in 3 h under a mild stirring of 300 rpm. Some well-designed experiments have been conducted, which show that the observed dye decompositions are directly related to the friction between BST nanoparticles and stirring rods in magnetic stirring. It is proposed that with the mechanical energy absorbed from friction, the BST nanoparticles have exerted a novel tribocatalytic effect for dye decompositions, which is confirmed by the detection of intermediate products of •OH and •O2− in stirring. These results clearly demonstrate that nanostructured oxides have the capability to harvest mechanical energy from ambient environment through friction for dye decomposition, which represents an important application for harvesting mechanical friction energy.