Enhanced tribocatalytic pollutant degradation through tuning oxygen vacancy in BaTiO3 nanoparticles

Abstract

Effective control of pathogen contamination is crucial for maintaining water security. This study investigated the impact of oxygen vacancys (OVs) content on the tribocatalytic performance of ferroelectric barium titanate (BTO) and its suitability as a tribocatalyst for water disinfection. The degradation efficiency of Rhodamine B (RhB) was increased by nearly 4-folds due to the appropriate OVs on the surface of BTO. In addition, experimental variables including the concentration of dissolved oxygen in the reaction solution, the temperature of reaction system, friction frequency, and charge transfer capacity were identified as important factors for tribocatalysis. Atom force microscope (AFM) imaging and density functional theory (DFT) calculations indicated that OVs couldn’t improve the electron transfer ability during BTO tribocatalysis. The excellent tribocatalytic performance of BTO-VO2 is due to the effective separation of electron and hole and the reduction of band gap. It is proposed that the tribocatalytic performance of BTO is determined by the electron transfer on the surface and the electron transition inside the catalyst. The simple stirring of BTO-VO2 tribocatalysts can effectively degrade organic molecules and inactivate model bacteria, which provides insights into the feasibility of wastewater treatment under dark conditions.