Eco-friendly, low-cost, and antibacterial PEM boosts microbial fuel cell performance: Power generation and wastewater treatment

The performance of microbial fuel cells (MFCs) relies significantly on the proton exchange membrane (PEM). While effective, commercial options like Nafion 117 are costly and possess inherent weaknesses. Improving methods of PEMs are generally used, requiring spending energy and money and causing harmful and toxic chemicals to enter the environment. This study introduces an innovative approach by enhancing sulfonated polyether sulfone (SPES) properties using Falcaria vulgaris extract, offering a simple, environmentally friendly, cost-effective solution. The resulting green functionalized SPES membranes (GFSPESs) were evaluated in dualchamber MFCs for energy production and textile wastewater treatment. SPES membranes were fabricated through a phase inversion process and subsequently functionalized using dip-coating, heating, and UV irradiation. Comprehensive analysis, including FTIR, EDS, SEM, and XPS, investigated the physicochemical structure of the PEMs. The plant extract exhibited notable benefits, enhancing hydrophilicity, proton conductivity, and antibacterial capability of the PEMs. The MFC with GFSPES-12 achieved a peak power output of 86.3 mW/m 2 and a maximum current of 327 mA/m 2 , surpassing the performance of Nafion 117 and the bare SPES membranes. GFSPES-12 also exhibited a maximum ion exchange capacity (1.89 meq/g) and proton conductivity (2.98 mS/cm). In textile wastewater treatment, the GFSPESs demonstrated improved COD removal (96.12 %) and higher coulombic efficiency (42.23 %). Notably, GFSPES-12 exhibited an antibacterial efficiency exceeding 93.5 %. These findings affirm the efficient functionality of GFSPES membranes in dual-chamber MFCs, offering a promising and sustainable alternative for energy production and wastewater treatment.