Binder-free NiO/MnO2 coated carbon based anodes for simultaneous norfloxacin removal, wastewater treatment and power generation in dual-chamber microbial fuel cell

Abstract

Norfloxacin (NFX) is a commonly consumed synthetic antibiotic drug to cure many adverse infectious diseases of humans worldwide, but their presence in almost all aquatic environments has grown into severe global health concerns. In this study, the power performance of dual-chamber microbial fuel cells (MFCs) with two different types of base anodes (graphite felt and activated carbon cloth) were tested with a coating of NiO/MnO2 for removal of NFX in wastewater. As transition metal oxides have excellent electrochemical stability and a higher specific capacitance, their application in MFC for antibiotic removal and wastewater treatment would be an interesting study. Four different NFX concentrations were studied in two different base material with a coating of NiO/MnO2. Coating was done with 2 step hydro solvothermal method and modified anode surface was characterized by XRD and XPS analyses. Extracellular electron transfer between microorganisms and the modified anode improved significantly as a consequence of reduced internal resistance and a more biocompatible surface as measured by Electroscopy Impedance Spectroscopy (EIS) and polarization curves. NiO/MnO2 coated graphite felt performed 1.2 fold better than the control plain graphite felt. Similar results were found for activated carbon cloth (ACC). Modified ACC performed 1.3 fold better than the control plain ACC.