TY - JOUR

T1 - Asymmetric reactors as an innovative approach for optimum microbial fuel cells performance

AU - Song, Bo

AU - Wang, Qi

AU - Ali, Jafar

AU - Wang, Zhibin

AU - Wang, Lei

AU - Wang, Jiahe

AU - Li, Jiaxin

AU - Glebov, Evgeni M.

AU - Zhuang, Xuliang

N1 - This work was supported by the National Natural Science Foundation of China (21976197, 42230411, and 42177099), the CAS International Partnership Program (grant number: 121311KYSB20200017), and the Fundamental Research Funds for the Central Universities (E1E40508X2).

PY - 2024/6

Y1 - 2024/6

N2 - Microbial fuel cells (MFCs) exhibit asymmetric overpotentials and redox potentials/rates at the cathode and anode. However, the impact of this asymmetric on power density and anode microbial community remains poorly understood. In this study, asymmetric reactors were designed for H-type MFCs to investigate this configuration. Contrary to the initial expectation of increased MFC power output with larger cathode volumes, it was unexpectedly found that the small-cathode reactor outperformed the large-cathode reactor, achieving a 61 % increase in maximum power density. Electrochemical characterization revealed a slightly lower charge transfer resistance (29.34 Ω) in the small-cathode reactor with carbon-felt anode biofilm in PBS. Moreover, 16S rRNA sequence analysis showed that the small-cathode reactor harbored a higher proportion of anaerobic bacteria (83 %), lower species diversity, and a higher abundance of exoelectrogens. Additionally, higher abundances of key gene modules (top eight), such as quinone oxidoreductase and citrate cycle, were observed in the small-cathode reactor. The anode biofilms in both reactors also synthesized some vitamins, such as menaquinone and thiamine. Furthermore, compared to the large-cathode reactor, each set of the small-cathode reactor saved ¥ 20, 23 g of borosilicate, and 55 mL of cathode electrolytes. This study sheds light on the interplay between reactor conformation and performance, contributing to the development of low-cost, high-performance MFCs for real field conditions.

AB - Microbial fuel cells (MFCs) exhibit asymmetric overpotentials and redox potentials/rates at the cathode and anode. However, the impact of this asymmetric on power density and anode microbial community remains poorly understood. In this study, asymmetric reactors were designed for H-type MFCs to investigate this configuration. Contrary to the initial expectation of increased MFC power output with larger cathode volumes, it was unexpectedly found that the small-cathode reactor outperformed the large-cathode reactor, achieving a 61 % increase in maximum power density. Electrochemical characterization revealed a slightly lower charge transfer resistance (29.34 Ω) in the small-cathode reactor with carbon-felt anode biofilm in PBS. Moreover, 16S rRNA sequence analysis showed that the small-cathode reactor harbored a higher proportion of anaerobic bacteria (83 %), lower species diversity, and a higher abundance of exoelectrogens. Additionally, higher abundances of key gene modules (top eight), such as quinone oxidoreductase and citrate cycle, were observed in the small-cathode reactor. The anode biofilms in both reactors also synthesized some vitamins, such as menaquinone and thiamine. Furthermore, compared to the large-cathode reactor, each set of the small-cathode reactor saved ¥ 20, 23 g of borosilicate, and 55 mL of cathode electrolytes. This study sheds light on the interplay between reactor conformation and performance, contributing to the development of low-cost, high-performance MFCs for real field conditions.

KW - Asymmetric Reactor

KW - Conformation

KW - Microbial Community

KW - Microbial Fuel Cell

KW - Power Density

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85191659970&origin=inward&txGid=b7d17dd0182dd998432609877b540903

UR - https://www.mendeley.com/catalogue/c52c441d-d054-38ca-8fc2-bfff699ccb77/

U2 - 10.1016/j.enconman.2024.118475

DO - 10.1016/j.enconman.2024.118475

M3 - Article

VL - 310

JO - Energy Conversion and Management

JF - Energy Conversion and Management

SN - 0196-8904

M1 - 118475

ER -