Photofragmentation of Ciprofloxacin: An Orchestrated Trident Attack Employing Activated Carbon Nanodot-Decorated Ti-Doped WO3 Nanodices

Abstract

Escalating infiltration of pharmaceutical pollutants into aquatic systems, particularly in freshwater and marine environments, has shot an arrow of menace at flora and fauna. In response, our study emphasizes efficient photocatalytic degradation of ciprofloxacin (CIP) using hydrothermally synthesized activated carbon nanodots (ACNDs)-decorated Ti-doped WO₃ nanodices in both freshwater (FW) and simulated seawater (SSW) environments. XRD and Raman confirm the formation of a monoclinic phase, whereas SEM reveals the distinctive nanodice morphology of WO₃. Under 1 Sun illumination, Ti-WO₃ ACNDs exhibited an exceptional degradation of CIP (93.83%) within 60 min, outperforming Ti-WO₃ and WO₃ samples. Intriguingly, under the SSW environment, Ti-WO₃ ACNDs manifested a degradation percentage of 85.10 and 59.61% at 5 and 10 ppm concentrations of CIP, respectively. Furthermore, the incorporation of ACNDs profoundly augments the donor density up to 27.27 folds in comparison to that of the Ti-doped WO₃. LC-MS chromatograms convincingly depict the successful defragmentation of CIP, indicating its transformation into less harmful products. Comprehensibly, our work highlights the pivotal role of ACNDs as “electron sinks” and offers mechanistic insights into accelerated CIP degradation in both freshwater and simulated seawater conditions spearheaded through a trident attack mechanism initiated by ^•OH radicals.