Novel oxygen vacancy-rich Bi2MoO6-SOVs/MgFe2O4 S-scheme heterojunction piezo-photocatalytic for efficient degradation of norfloxacin and theoretical calculations

Abstract

Magnetic materials introduced into semiconductor catalysts greatly compensate for the traditional powder catalysts’ disadvantages of difficult recovery and low reuse rate. A series of oxygen vacancy-rich Bi2MoO6-SOVs/MgFe2O4 nanomicrospheres are prepared by stepwise synthesis. By simulating visible light irradiation and ultrasonic co-illumination to degrade norfloxacin (NOR) to evaluate the piezo-photocatalytic performance of the samples, the Bi2MoO6-SOVs/MgFe2O4-15 % has a degradation efficiency of 96.8 % within 30 min and high chemical stability. This method not only improves the limitations of finite free electrons in piezoelectric catalysis but also effectively suppresses the rapid recombination of photogenerated electrons-holes in photocatalysis. To improve the practical application of this catalyst, we also consider the effects of pH, co-existing ions in water and different water matrices on NOR degradation. In situ X-ray photoelectron spectroscopy (ISI-XPS) and density functional theory (DFT) calculations further confirm the existence of an S-scheme charge transfer mechanism and oxygen vacancies (SOVs).