Assessment of tapioca-synthesized graphene-modified electrode with biopolymer-based membrane for enhancing biofilm efficiency in microbial fuel cell

Microbial fuel cells hold enormous potential for waste management, energy production, and biomass valorization. However, technical challenges exist, including low power generation efficiency and operational stability. Graphene is an innovative material with remarkable physical and chemical properties that can enhance the advancement of microbial fuel cells (MFC). This study utilized tapioca (cassava starch) as a novel precursor for graphene synthesis via a chemical exfoliation method.. The anode electrodes were coated with graphene and integrated into the MFC system, combining cellulose acetate films as proton exchange membranes to allow the movement of ions. Their effect on bioelectricity generation was explored using a two-chambered microbial fuel cell reactor and their biofilm efficiency was determined. A mixed culture of three active bacteria (Pseudomonas taiwanensis, Myroids odoratimimus, and Spingobacterium mizutai) was used as a biocatalyst. Membrane efficacy was assessed using SEM and EDX analysis. The graphene-coated copper electrode demonstrated a biofilm efficiency of 5.10%, resulting in higher energy output with a peak voltage generation of 2.5V, outperforming non-coated electrodes. Comparative SEM images showed the thicknesses of the support layers of cellulose acetate membranes before the experiment and the thickness and porosity sizes reduced over time. The study shows tapioca-synthesized graphene-modified electrodes and cellulose acetate membranes can significantly improve Microbial fuel cell performance. The modification enhances electrode conductivity and biofilm growth, while the cellulose acetate membrane supports proton conductivity, indicating potential for scaling up MFC technology.