Powerful combination of FeWO4/g-C3N4 heterostructures for solar light driven photocatalytic degradation of tetracycline and its antibacterial activity

Abstract

In light of growing ecological concerns stemming from extensive antibiotic use, there is an urgent call to develop efficient methods for reducing antibiotics in pharmaceutical wastewater. Photocatalysis, a well-established advanced oxidation technology, is a key contender in this endeavor, drawing increasing attention to semiconductor photocatalysts. This study investigates the kinetics and mechanisms of photocatalytic tetracycline (TC) decomposition using in-situ synthesized FeWO4/g-C3N4 heterostructures (FGC Hs) as photocatalysts. The nanocomposites were thoroughly characterized using various optoelectronic spectroscopies. XRD and HRTEM studies confirmed the formation of crystalline monoclinic structure FGC Hs. Under simulated sunlight, FGC Hs exhibited outstanding performance in photocatalytic degradation and tetracycline adsorption, achieving a remarkable 95 % removal rate within just 160 min at a rate of 0.99 min−1. Additionally, FGC Hs proved easily recoverable, displayed excellent stability, and demonstrated recyclability, indicating significant potential for developing new sunlight-driven photocatalysts. Furthermore, this study proposes a photocatalytic degradation mechanism based on radical trapping experiments, revealing the pivotal roles of hydroxyl (HO∙) and hole (h+) species in the degradation of TC over FCG Hs. These findings highlight the promising application of these synthesized heterostructures in sunlight-driven TC degradation and their ability to meet the stringent requirements for antibiotic removal from pharmaceutical wastewater treatment processes.