Black phosphorus quantum dots regulate electronic structure of perovskite catalyst for enhanced peroxodisulfate activation and non-radical decontamination

Abstract

A regulatory strategy for tuning electronic structure of perovskite-type materials was proposed by attaching black phosphorus quantum dots (BPQDs) for enhancing peroxodisulfate (PDS) activation. BPQDs obtained by ultrasonic exfoliation were used for one-step hydrothermal preparation of BiFeO3 (BFO) containing in-situ growth of silver nanoparticles. The catalyst could achieve complete removal of sulfadiazine within 5 min, accounting for oxidation rate as high as 0.82 min−1. Both experimental and theoretical results revealed that non-radical electron transfer relevant to electronic structure played a decisive role. BPQDs triggered electron rearrangement between BFO and Ag, thereby contribution of d-orbital of Fe and Ag near Fermi level was enhanced for increasing conductive carriers and electron mobility. Under synergetic action of BPQDs, BFO and Ag, Bi and Fe, adsorption of negatively charged S2O82- was enhanced. The outcomes provide a proof-in-concept demonstration of BPQDs for modifying electronic structure of catalyst to enhance removal of emerging contaminants in water.