The enhancement of microbial fuel cell performance by anodic bacterial community adaptation and cathodic mixed nickel-copper oxides on a graphene electrocatalyst.

Autor: Khater DZ; Chemical Engineering & Pilot Plant Department, Engineering and Renewable Energy Research Institute, National Research Centre, 33 El-Buhouth St., Dokki, Cairo, 12311, Egypt., Amin RS; Chemical Engineering & Pilot Plant Department, Engineering and Renewable Energy Research Institute, National Research Centre, 33 El-Buhouth St., Dokki, Cairo, 12311, Egypt., Zhran MO; Faculty of Science (Girls), Botany and Microbiology Department, Al-Azhar University, Nasr City, Cairo, Egypt., Abd El-Aziz ZK; Faculty of Science (Girls), Botany and Microbiology Department, Al-Azhar University, Nasr City, Cairo, Egypt., Mahmoud M; Water Pollution Research Department, National Research Centre, 33 El-Buhouth St., Dokki, Cairo, 12311, Egypt., Hassan HM; Microbial Chemistry Department, National Research Centre, 33 El-Buhouth St., Dokki, Cairo, 12311, Egypt., El-Khatib KM; Chemical Engineering & Pilot Plant Department, Engineering and Renewable Energy Research Institute, National Research Centre, 33 El-Buhouth St., Dokki, Cairo, 12311, Egypt. kamelced@hotmail.com.
Jazyk: angličtina
Zdroj: Journal, genetic engineering & biotechnology [J Genet Eng Biotechnol] 2022 Jan 24; Vol. 20 (1), pp. 12. Date of Electronic Publication: 2022 Jan 24.
DOI: 10.1186/s43141-021-00292-2
Abstrakt: Background: Although microbial fuel cells (MFCs) represent a promising technology for capturing renewable energy from wastewater, their scaling-up is significantly limited by a slow-rate cathodic oxygen reduction reaction (ORR) and the development of a resilient anodic microbial community. In this study, mixed transition metal oxides of nickel and copper (Ni and Cu), supported on a graphene (G) (NiO-CuO/G) electrocatalyst, were synthesized and tested as a cost-effective cathode for ORR in MFCs. Electrochemical measurements of electrocatalyst were conducted using a rotating disk electrode (RDE) and linear sweep voltammetry (LSV) in a neutral electrolyte, and compared with a benchmark Pt/C catalyst. Furthermore, the long-term performance of the as-synthesized electrocatalyst was evaluated in a single-chamber MFC by measuring organic matter removal and polarization behavior. The successful enrichment of electroactive biofilm was also monitored using transmission electron microscopy and the Vitek2 compact system technique.
Results: When compared with the benchmark platinum cathode, the NiO-CuO/G electrocatalyst exhibited high selectivity toward ORR. The rotating disk electrode (RDE) experiments reveal that ORR proceeds via a 4-electron ORR mechanism. Furthermore, the NiO-CuO/G electrocatalyst also exhibited a high power density of 21.25 mW m -2  in an air-cathode MFC, which was slightly lower than that of Pt/C-based MFC (i.e., 50.4 mW m -2 ). Biochemical characterization of the most abundant bacteria on anodic biofilms identified four genera (i.e., Escherichia coli, Shewanella putrefaciens, Bacillus cereus, and Bacillus Thuringiensis/mycoides) that belonged to Gammaproteobacteria, and Firmicutesphyla.
Conclusions: This study demonstrates that the NiO-CuO/G cathode had an enhanced electrocatalytic activity toward ORR in a pH-neutral solution. This novel mixed transition metal oxide electrocatalyst could replace expensive Pt-based catalysts for MFC applications.
(© 2022. The Author(s).)
Databáze: MEDLINE
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