Optimization of Microbial Fuel Cell Performance Using Agricultural Waste-Derived Carbon Electrodes for Sustainable Bioelectricity Generation

Abstract

Microbial fuel cells can be considered a sustainable technology in wastewater treatment and electricity production; however, the low power density, costly electrodes, and unpredictable operation performance have prevented practical use. In this research, agricultural waste-based carbon electrodes are investigated, and the current study attempts to present an evidence-based optimization approach for materials selection and electrochemical performance through investigating the following aspects: electrode fabrication, carbonization temperature, chemical activation, power density, and chemical oxygen demand (COD) removal efficiency. In the reviewed devices, the highest power densities were between 26 and 2171 mW m⁻². The graphitized mango-seed carbon generated 2171 mW m⁻², whereas the Datura peel biochar generated 584 mW m⁻² power density with COD removal efficiency of 85.4%. In addition, increasing the graphitization temperature of mango-seed from 1000 to 1100 °C increased power density from 1351 to 2171 mW m⁻². Cathode modification enhanced the obtained power density from 542 to 2178 mW m⁻² using similar experimental conditions. The results obtained through comparison show that carbonization temperature, activation techniques, electrode loading, compaction, and cathode setup are key variables affecting optimization. The suggested model considers all the aforementioned variables, electricity production, and wastewater treatment analysis. Waste agricultural products-based carbon electrodes have shown promise as a sustainable source of energy, but there is need for further research before implementing them in actual wastewater treatment plants.