Dual functional rGO/Fe3O4/PANI nanocomposite anodes for enhanced performance of microbial fuel cells

Abstract

A dual chamber microbial fuel cells was developed using biomass derived reduced graphene oxide (E-rGO) synthesized from Ensete ventricosum corm waste as an anode material for simultaneous bioelectricity generation and heavy metal remediation. To enhance electrochemical performance, an E-rGO/Fe3O4/PANI NC anode was fabricated and evaluated for the removal of Cr (VI) and Pb (II) from wastewater. Incorporation of Fe3O4 NP and polyaniline improved electrical conductivity, surface characteristics, and interfacial charge transfer properties. Structural, morphological, optical, and thermal properties of the materials were characterized using UV-vis, SEM, XRD, FTIR, Raman spectroscopy, and TGA, while electrochemical behavior was examined by cyclic voltammetry and electrochemical impedance spectroscopy. The E-rGO/Fe3O4/PANI anode achieved Cr (VI) and Pb (II) removal efficiencies of 88% and 86%, respectively, compared with 74% and 68% for pristine E-rGO. The E-rGO/Fe3O4/PANI nanocomposite electrode also generated a maximum power density of 65 mW m−2 and a current density of 1312 mA m−2, representing a significant improvement over the E-rGO anode (8.55 mW m−2 and 612 mA m−2 under identical operating conditions. While the power density is moderate compared with highly optimized laboratory scale MFC systems, the results demonstrate enhanced performance in a system designed for concurrent wastewater treatment and energy recovery. These findings indicate that biomass derived graphene based nanocomposites can serve as sustainable and effective electrode materials for integrated heavy metal remediation and bioenergy generation in microbial fuel cell systems.