BaTiO3/FeOCl composite as highly efficient Piezo-Photo-Fenton catalyst for the degradation of tetracycline hydrochloride

In recent years, an increasing amount of drug pollutants such as antibiotics have been entering the water environment, and conventional water treatment technologies struggle to decompose these persistent organic contaminants. In response to the above situation, this study utilized a partial pyrolysis method to synthesize a novel type of BaTiO 3 /FeOCl heterostructure catalyst, and established a Piezoelectric-Photo-Fenton catalytic system to achieve effective degradation of tetracycline hydrochloride (TCH). With concurrent exposure to visible light radiation and ultrasonic excitation, the BaTiO 3 /FeOCl system achieved complete degradation of TCH within 6 min, demonstrating significantly superior performance compared to individual components or single-process systems. Moreover, the system exhibited broad pH adaptability and excellent operational stability, and quantitative detection and radical trapping confirmed •OH and •O 2 − as the principal reactive oxygen species. Mechanism studies demonstrated that the intrinsic piezoelectric field of BaTiO 3 promotes charge carrier decoupling and boosts the turnover of the Fe 3+ /Fe 2+ redox couple, while FeOCl served as an active site for H 2 O 2 activation, thereby synergistically leading to the abundant formation of reactive oxygen species (•OH and •O 2 − ). This work presents an effective strategy for integrating piezoelectric, photocatalytic, and Fenton processes to enhance catalytic efficiency, presenting a highly prospective strategy for the purification of organically polluted wastewater.