An effective, novel and low-cost proton exchange membrane for microbial fuel cell-based bioelectricity production

Abstract

Microbial Fuel Cells (MFCs) are a substitute for fossil-fuel-based electricity generation. They are innovative bioelectrochemical systems that use microbial catalysts to convert organic waste directly into electrical energy. However, MFCs face several commercialization challenges, including expensive Proton Exchange Membranes (PEMs), making them unaffordable. The present research aims to develop cost-effective, environmentally friendly, high-performance PEM to make MFC technology more viable. The study analyzed using MFCs with different PEMs with native microflora and Serratia marcescens (AATB1) as biocatalysts to produce bioelectricity and treat septic tank wastewater (STWW). The experiment included a control group with sterile STWW. The study involves fabricating and characterizing the optimized Novel Cement Supported Conductive Salts PEM (NCSCS PEM) using SEM, TGA, and EIS techniques. The commercial Nafion 117 and salt bridge were used to compare NCSCS PEM in MFCs. The anode biofilm was investigated using CV, CLSM, and SEM. The MFCs with Nafion 117, NCSCS PEM, and Salt bridge produced power densities of 126.6 ± 1.06 mW/m², 204.04 ± 0.87 mW/m², and 188.26 ± 1.13 mW/m², respectively. Moreover, Our study shows a greater PEM cost reduction with commercial Nafion 117 PEM in terms of consumed cost of $7.04, $0.21, and $2.41 for making MFCs with Nafion 117 (9 cm²), NCSCS PEM (15 cm³) (with 97.02 % reduced cost) and salt bridge (15 cm³) (with 65.77 % reduced cost) respectively. Our MFC setup cost was reduced by 70.29 % by replacing Nafion 117 with durable NCSCS PEM. Using our cost-effective, better-performing, durable NCSCS in MFC makes the MFC technology or any other technology that needs PEM feasible on a larger scale.