Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes

Handle URI:
http://hdl.handle.net/10754/597480
Title:
Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes
Authors:
Ahn, Yongtae; Zhang, Fang; Logan, Bruce E.
Abstract:
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.
Publisher:
Elsevier BV
Journal:
Journal of Power Sources
KAUST Grant Number:
KUS-I1-003-13
Issue Date:
Feb-2014
DOI:
10.1016/j.jpowsour.2013.08.084
Type:
Article
ISSN:
0378-7753
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).
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorAhn, Yongtaeen
dc.contributor.authorZhang, Fangen
dc.contributor.authorLogan, Bruce E.en
dc.date.accessioned2016-02-25T12:40:34Zen
dc.date.available2016-02-25T12:40:34Zen
dc.date.issued2014-02en
dc.identifier.citationAhn 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.en
dc.identifier.issn0378-7753en
dc.identifier.doi10.1016/j.jpowsour.2013.08.084en
dc.identifier.urihttp://hdl.handle.net/10754/597480en
dc.description.abstractTo 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.en
dc.description.sponsorshipThe 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).en
dc.publisherElsevier BVen
dc.subjectAir cathodeen
dc.subjectHumidityen
dc.subjectLinear sweep voltammetryen
dc.subjectMicrobial fuel cellen
dc.subjectWater floodingen
dc.titleAir humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodesen
dc.typeArticleen
dc.identifier.journalJournal of Power Sourcesen
dc.contributor.institutionPennsylvania State University, State College, United Statesen
kaust.grant.numberKUS-I1-003-13en
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