Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes
Type
ArticleAuthors
Ahn, Yongtae
Zhang, Fang

Logan, Bruce E.
KAUST Grant Number
KUS-I1-003-13Date
2014-02Permanent link to this record
http://hdl.handle.net/10754/597480
Metadata
Show full item recordAbstract
To better understand how air cathode performance is affected by air humidification, microbial fuel cells were operated under different humidity conditions or water pressure conditions. Maximum power density decreased from 1130 ± 30 mW m-2 with dry air to 980 ± 80 mW m -2 with water-saturated air. When the cathode was exposed to higher water pressures by placing the cathode in a horizontal position, with the cathode oriented so it was on the reactor bottom, power was reduced for both with dry (1030 ± 130 mW m-2) and water-saturated (390 ± 190 mW m-2) air. Decreased performance was partly due to water flooding of the catalyst, which would hinder oxygen diffusion to the catalyst. However, drying used cathodes did not improve performance in electrochemical tests. Soaking the cathode in a weak acid solution, but not deionized water, mostly restored performance (960 ± 60 mW m-2), suggesting that there was salt precipitation in the cathode that was enhanced by higher relative humidity or water pressure. These results showed that cathode performance could be adversely affected by both flooding and the subsequent salt precipitation, and therefore control of air humidity and water pressure may need to be considered for long-term MFC operation. © 2013 Elsevier B.V. All rights reserved.Citation
Ahn Y, Zhang F, Logan BE (2014) Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes. Journal of Power Sources 247: 655–659. Available: http://dx.doi.org/10.1016/j.jpowsour.2013.08.084.Sponsors
The research reported here was supported by the Siemens Corporation and Award KUS-I1-003-13 from the King Abdullah University of Science and Technology (KAUST).Publisher
Elsevier BVJournal
Journal of Power Sourcesae974a485f413a2113503eed53cd6c53
10.1016/j.jpowsour.2013.08.084