Discovering of the photocatalytic performance of BiFeO3/BNQDs immobilized polyester filters for efficient continuous-flow elimination of recalcitrant antibiotic via PMS activated process

Abstract

Finding effective and practical elimination systems for harmful contaminants is a challenging issue and thereby, construction of scalable materials has gained attention in advanced oxidation processes. Herein, BiFeO3 (BFO) perovskites were first incorporated with boron nitride quantum dots (BNQDs) via impregnation technique and then the BFO/BNQDs catalysts were immobilized on commercial polyester (PE) filters via dip-coating method (BFO/BNQDs@PE). It was aimed to enhance the photocatalytic performance of perovskite catalyst via incorporation of BNQDs and restrict the disadvantages of powder form of catalysts via immobilization on filter. SEM images revealed that the BFO/BNQDs particles were uniformly coated on the polyester fiber. The XRD pattern demonstrated that the immobilization process did not alter the crystal structure of perovskite. The catalytic performance of the system was investigated via degradation of tetracycline-hydrochloride (TC-HCl) in batch as well as continuous flow conditions and the dual-effect catalytic system was generated by introducing peroxymonosulfate (PMS) agent to the antibiotic solution. The TC-HCl degradation efficiencies under PMS-activated system were calculated as 49.3% and 70% for BFO@PE and BFO/BNQDs@PE, respectively. The high-efficiency removal was assigned to the hindered recombination rate owing to electron capturing ability of PMS and quantum confinement effect of BNQDs. In addition, the immobilization of BFO/BNQDs particles on PE filter enabled more active surface sites for the target TC-HCl molecules, resulting enhanced photodegradation efficiency. The photocatalytic degradation mechanism was explained in detail and the reusability of catalytic filters was investigated. Under flow conditions, 91.3% removal was still achieved by BFO/BNQDs@PE catalytic filter until 7 h of visible light irradiation, verifying successful immobilization of BFO/BNQDs particles as well as its high reusability. This study contributes to the hybridization of quantum dots with scalable materials for treatment of recalcitrant pollutants with industrial interest.