Waste-derived nanocomposites powering the future: Biochar@Fe₂O₃ anodes in microbial fuel cells

This research presents the combination of chir pine-derived biochar and petunia-derived ferric oxide (Fe₂O₃) as nanocomposites acting as catalysts for the anode, enhancing the functionality of a microbial fuel cell (MFC). Improved microbial activity and electron transport were the aim of this combination. The nanocomposite was examined using a variety of techniques, such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The synthesised nanocomposites were used as a catalyst on the anode electrode. The anode with nanocomposite showed an improved performance compared to the unmodified or bare anode and the anode with only biochar. The charge-discharge study, polarisation study, cyclic voltammetry, electrochemical impedance spectroscopy, Coulombic efficiency, and other techniques were used to accomplish the electrochemical investigation. The testing results showed significant improvements in power density of up to 13.32 W/m³, highlighting the composite's potential to boost MFC efficiency. The improved biofilm formation was observed using increasing concentrations of biochar@Fe₂O₃ nanocomposites. The energy recovered as bioelectricity was around 16.34%. Owing to the abundance of Chir Pine biomass and iron-rich Petunia plants, this green-synthesized nanocomposite offers a low-cost and scalable approach for simultaneous wastewater treatment and clean energy generation, aligning with circular economy and sustainability goals.