Possible bio cathode materials for usage in microbial fuel cells towards energy generation and wastewater treatment to sustain environment: A review
S. Baskar, J. Jayaprabakar, Arasu Raman, T. Surulivel Rajan, J. Aravind Kumar, Nalini Ramachandran U, E. Balaji, S. Padmanabhan, Jisha PK, M. Ruban
Abstract
• This paper discusses the promising bio-cathode materials in microbial fuel cells (MFCs) for renewable energy and wastewater treatment, outlining the advantages and challenges. • It reviews the design of MFC systems and includes the recent innovations in dual-chamber and hybrid designs, fabricated with stainless steel and graphite preferentially to achieve better organics degradation efficiencies. • The work shows that microbial fuel cells can generate electricity from organic waste while treating wastewater very well. • Scalability issues and cost issues, along with the future perspectives on research required for the development of bio-cathodes and the prospects for larger-scale bio-cathodes for industrial applications. The aim of this study is to review the effectiveness of bio-cathode materials usage in microbial fuel cells (MFCs) for power generation and wastewater treatment. The review focused on the Microbial fuel cell construction and design. The Anode and cathode materials of MFCs with their merits and demerits are compared. The first half of the study discusses the components for Anodes and cathodes. Typical anode and cathode materials are compared based on their power densities. The focus is narrowed down to discuss about bio cathode components and their materials including the most prominent/discussed ones such as Stainless steel and Graphite/carbon as bio cathode materials. Indirect electron transfer and direct electron transfer in MFCs are also reviewed. The second part of the review focused on bio cathode materials for electricity production and wastewater treatment. It was reported in many literatures that, MFCs can serve as supplementary, decentralized power sources. Also this review highlighted that MFCs can be employed with effective methods for removing sulfides from wastewater with certain microbes. It was reported that, a considerable coulombic efficiency of 80% can be achieved with MFCs. It was also found from the literatures that a well-designed MFC-membrane bioreactor for wastewater treatment could achieve good pollutant removal performance with a remarkable power density of 6 W/m 3 at an average current of 0.4 mA to 1.9 mA. The limitations of current technology, as well as some possible future developments, were discussed in the last section. Therefore, this may open up possibilities for further development and the use of bio-cathode materials in the future.