Recent Modifications of Anode Materials and Performance Evaluation of Microbial Fuel Cells: A Brief Review

Abstract

A microbial fuel cell is a bioelectrochemical device that uses different electroactive microorganisms to produce electricity from waste. Its anode is a key component because the extracellular electron transport at the interface of the anode and anolyte influences the overall operation and performance. The effectual extracellular electron transport depends on the thickness and strength of the microbial biofilm formed on the anodic surface. The biofilm should be conductive for the suitable anode potential, half-cell resistance, substrate degradation, and overall cell stability. To achieve the required properties of the biofilm, the anode should have specific material properties that are not embedded in a single material. Modifying the anode material is the best option to achieve the required properties. Many research groups have experimented with different anode modifications like surface treatment, variation of traditional carbonaceous anode materials, fabrication of composite materials, development of biomass-based anodes that mimic the traditional anodes, and hybridization. This review summarizes different anodes and their modifications to enhance the overall performance of microbial fuel cells. The anode modifications are numerous and nonspecific. Different materials, methods, and mechanisms confuse the ultimate objectives. Therefore, separating the types of materials used for the anode modifications and their comparative study describes the actual underlying difficulties, mechanisms behind the microbial fuel cell operation, and perspectives for future research in the field. This article highlights the deficiencies in traditional anodes and their recent modifications, comparative evaluations of anode modifications on microbial fuel cell performance, challenges in the scaled-up microbial fuel cell operation, and future research perspectives.

Topics & Concepts