A novel Fe-PTFE magnetic composite prepared by ball milling for the efficient degradation of imidacloprid: Insights into interaction mechanisms based on ultrasonic piezoelectric catalysis

Abstract

In this study, a novel magnetic poly (tetrafluoroethylene, PTFE) (Fe@PTFE) piezoelectric catalytic material was successfully prepared by a simple ball milling treatment. The prepared piezoelectric catalytic material Fe@PTFE exhibited excellent catalytic performance under the activation of ultrasonic (US) and realized the efficient degradation of imidacloprid (IMI) at low concentrations in an aqueous environment. It was demonstrated by various characterization methods that Fe0 was successfully loaded onto PTFE particles (1–15 μm) by ball milling. The US/Fe@PTFE system exhibited superior IMI degradation efficiency (99 %) and degradation rate (7.81× 10−2 min−1) under ultrasonic polarization with high efficiences of IMI degradation after five cycles. In addition, the system maintained excellent removal efficiencies in the real water matrixes. The mechanism study demonstrated that Fe@PTFE generated a variety of reactive oxygen species (•OH, 1O2 and O2•-) and H2O2 under the irradiation of US, and the production of H2O2 provided the conditions for the continuation of the Fenton-like reaction. Furthermore, the presence of O2•- in the system enhanced the recycling efficiency of Fe(III) and Fe(II), which further enhanced the degradation efficiency of the Fenton-like process. This study provides a novel perspective on a PTFE-based ultrasonic piezoelectric catalytic system for the efficient removal of organic pollutants in the environmental field.