Electrode materials for microbial fuel cells: nanomaterial approach

Abstract

Microbial fuel cell (MFC) technology has the potential to become a major renewable energy resource by degrading organic pollutants in wastewater. The performance of MFC directly depends on the kinetics of the electrode reactions within the fuel cell, with the performance of the electrodes heavily influenced by the materials they are made from. A wide range of materials have been tested to improve the performance of MFCs. In the past decade, carbon-based nanomaterials have emerged as promising materials for both anode and cathode construction. Composite materials have also shown to have the potential to become materials of choice for electrode manufacture. Various transition metal oxides have been investigated as alternatives to conventional expensive metals like platinum for oxygen reduction reaction. In this review, different carbon-based nanomaterials and composite materials are discussed for their potential use as MFC electrodes.

Air Breathing Cathodes for Microbial Fuel Cell using Mn-, Fe-, Co- and Ni-containing Platinum Group Metal-free Catalysts

“…In order to enhance the ORR kinetics, usually three different pathways can be selected for integration of catalysts into the cathode layer. The first one is the utilization of high surface area carbons like activated carbon (AC) [27], [28], graphene-based materials [29], carbon nanotubes (CNTs) [30], carbon nanofibers (CNFs) [31] or nitrogen doped carbon [32]. Activated carbon seems to be the best compromise between cost and performances and lately it has been largely utilized as a cathode in MFCs [32].…”

Bimetallic platinum group metal-free catalysts for high power generating microbial fuel cells

“…Recently the usage of carbonaceous materials like activated carbon (AC) [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], carbon nanotubes (CNT) [54], [55], carbon nanofibers (CNF) [56], [57], [58], [59], graphene [60], [61], [62], [63] and modified carbon black [64], [65] in the cathodes has greatly increased. Those materials possess high surface area, electrical conductivity, mechanical strength and resistance to corrosion, moreover they are commercially readily available and very economical to use for large-scale applications [66]. Unfortunately, carbonaceous materials still have high overpotentials and low reaction kinetics, which restrain its usage as the cathode material.…”

Carbon-Based Air-Breathing Cathodes for Microbial Fuel Cells

“…Another alternative is the use of inorganic based catalysts, such as iron, cobalt, nickel, or manganese [39]. However, the most common materials used for cathode electrodes in MFCs are carbon-based which, besides following the peroxide pathway, offers a high conductivity, high durability, high mechanical strength, and high surface area at an affordable cost [40][41][42]. A cathode electrode usually consists of the catalyst layer and the supporting material, which generally acts as the diffusion layer, as well as the current collector.…”