The Synergetic Enhancement of Piezo Catalytic Performance to Remove Tetracycline by K2Ti6O13/TiO2 Composite

Piezo catalysis has recently been considered an important technology in environmental treatment. In this study, a type II heterojunction of K 2 Ti 6 O 13 /TiO 2 composite is successfully prepared by a hydrothermal method for the highly efficient piezo catalytic degradation of tetracycline. The factors influencing the piezo catalysis of tetracycline are systematically studied and discussed, including pH value, competition of anions/cations, ultrasonic power, ultrasonic frequency, and temperature, etc. Free radical sacrificial agents (EDTA-2Na, DMSO, AgNO 3 , and P-BQ, etc.) are utilized to better understand the degradation mechanism by piezo catalysis, and holes are found to play a dominant role in the catalytic process, and ·O 2 - comes the second. The combination of K 2 Ti 6 O 13 and TiO 2 constructs a type II heterojunction of the highly efficient separation of piezo electrons and holes, thus systematically increasing the piezo catalytic performance. This work provides a new idea to degrade organic pollution through piezo catalysis and the potential application of piezo catalysis in environmental treatment. The K 2 Ti 6 O 13 /TiO 2 heterojunction is constructed to improve the piezo catalytic performance of tetracycline. • The synergetic enhancement of the piezo catalysis of K 2 Ti 6 O 13 /TiO 2 nanocomposite. • The enhancement of the piezo catalysis is due to the band gap engineering. • the mechanism of the piezo catalysis is systematically investigated.