<p>Conventional Nafion membranes presented substantial challenges in microbial fuel cells due to its high cost, reduced power performance under dry conditions, high temperature requirement, and mechanical instability because of biofouling. Therefore, new materials increased the need to enhance ionic conductivity, mechanical stability, and reduced cost of microbial fuel cell membranes for different applications comprising wastewater treatment and energy production. In present work, polybenzimidazole due to its high mechanical strength and proton conductivity was incorporated in varied concentrations of ceramic materials such as kaolinite and montmorillonite (5 wt%, 10 wt% and 15 wt%) by solution casting method utilizing doctor blade. The polybenzimidazole-kaolinite-montmorillonite membranes were analyzed by employing various techniques including scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffraction, and electrochemical impedance spectroscopy. In addition, other properties included proton conductivity, water uptake capacity, and swelling ratio were also evaluated to assess the use of these membranes in microbial fuel cells fed with sugar wastewater. The results of the study revealed that the 10 wt% clay content with polybenzimidazole showed high proton conductivity of 0.82 S cm⁻¹ substantially higher than other polymer–clay composites (0.045 S cm⁻¹ to 0.032 S cm⁻¹) reported in the literature, peak power density of 3334.1 mW m⁻², 28% water uptake capacity, and tensile strength of 135 ± 3&#xa0;MPa in microbial fuel cell system. The synergy between these membrane and sugar wastewater embedded MFC system resulted in an enhanced proton conductivity, water retention, mechanical stability, and efficient wastewater treatment, thereby creating a more effective solution for MFC applications.</p> Graphical abstract <p></p>