BAGSPl of mesoporous Ag/ZnO nanostructures for visible light mediated photocatalytic removal of ciprofloxacin from water; a morphological perspective

Abstract

Presence of antibiotics like ciprofloxacin (CIPRO) in drinking water resources has become a serious concern worldwide. Persistent existence of CIPRO in water environment leads to higher antimicrobial resistance by aiding the development of new and virulent bacterial strains. With the help of semiconductor based photocatalysts along with suitable metal doping, here we present, the successful synthesis of ZnO and Ag/ZnO nanocomposites derived from biosource for the active degradation of CIPRO from water through visible radiation. ‘Bio-source assisted green synthesis’ (BAGS) strategy has been followed using plantain-banana Musa balbisiana pseudostem (MBP) fibers for the successful replication of ZnO and Ag/ZnO mesoporous tubular-structured nanocomposites (NCs). Mesoporous morphological structures have been achieved in all three-weight percentages (wt%) of Ag/ZnO NCs (2, 5 and 10 wt%). The as-obtained bare and Ag/ZnO mesoporous tubular nanostructures are studied via XRD, UV-VIS, FT-IR, SEM and BET techniques. Out of three wt%, 5Ag/ZnO NCs better performed in the photocatalytic degradation of CIPRO under visible illumination (∼76%). Crystallite size, morphology and enhanced surface area have played crucial role in their photocatalytic mechanism. 5Ag/ZnO NCs are highly effective in CIPRO degradation even after five repeat cycles. Through LC-MS intermediate analysis, quinolone moiety-based pathway for CIPRO degradation is proposed. These bioderived NCs would pave a sustainable pathway for visible photocatalysis of emerging organic pollutants.