Assessment of four different cathode materials at different initial pHs using unbuffered catholytes in microbial electrolysis cells

Handle URI:
http://hdl.handle.net/10754/597612
Title:
Assessment of four different cathode materials at different initial pHs using unbuffered catholytes in microbial electrolysis cells
Authors:
Ribot-Llobet, Edgar; Nam, Joo-Youn; Tokash, Justin C.; Guisasola, Albert; Logan, Bruce E.
Abstract:
Nickel foam (NF), stainless steel wool (SSW), platinum coated stainless steel mesh (Pt), and molybdenum disulfide coated stainless steel mesh (MoS 2) electrodes have been proposed as catalysts for hydrogen gas production, but previous tests have primarily examined their performance in well buffered solutions. These materials were compared using two-chamber microbial electrolysis cells (MECs), and linear sweep voltammetry (LSV) in unbuffered saline solutions at two different initial pHs (7 and 12). There was generally no appreciable effect of initial pH on production rates or total gas production. NF produced hydrogen gas at a rate of 1.1 m3 H2/m 3·d, which was only slightly less than that using Pt (1.4 m3 H2/m3·d), but larger than that obtained with SSW (0.52 m3 H2/m3·d) or MoS2 (0.67 m3 H2/m3·d). Overall hydrogen gas recoveries with SSW (29.7 ± 0.5 mL), MoS2 (28.6 ± 1.3 mL) and NF (32.4 ± 2 mL) were only slightly less than that of Pt (37.9 ± 0.5 mL). Total energy recoveries, based on the gas produced versus electrical energy input, ranged from 0.75 ± 0.02 for Pt, to 0.55 ± 0.02 for SSW. An LSV analysis showed no effect of pH for NF and Pt, but overpotentials were reduced for MoS2 and SSW by using an initial lower pH. At cathode potentials more negative than -0.85 V (vs Ag/AgCl), NF had lower overpotentials than the MoS2. These results provide the first assessment of these materials under practical conditions of high pH in unbuffered saline catholytes, and position NF as the most promising inexpensive alternative to Pt.
Citation:
Ribot-Llobet E, Nam J-Y, Tokash JC, Guisasola A, Logan BE (2013) Assessment of four different cathode materials at different initial pHs using unbuffered catholytes in microbial electrolysis cells. International Journal of Hydrogen Energy 38: 2951–2956. Available: http://dx.doi.org/10.1016/j.ijhydene.2012.12.037.
Publisher:
Elsevier BV
Journal:
International Journal of Hydrogen Energy
KAUST Grant Number:
KUS-I1-003-13
Issue Date:
Mar-2013
DOI:
10.1016/j.ijhydene.2012.12.037
Type:
Article
ISSN:
0360-3199
Sponsors:
This work was supported by 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.authorRibot-Llobet, Edgaren
dc.contributor.authorNam, Joo-Younen
dc.contributor.authorTokash, Justin C.en
dc.contributor.authorGuisasola, Alberten
dc.contributor.authorLogan, Bruce E.en
dc.date.accessioned2016-02-25T12:43:03Zen
dc.date.available2016-02-25T12:43:03Zen
dc.date.issued2013-03en
dc.identifier.citationRibot-Llobet E, Nam J-Y, Tokash JC, Guisasola A, Logan BE (2013) Assessment of four different cathode materials at different initial pHs using unbuffered catholytes in microbial electrolysis cells. International Journal of Hydrogen Energy 38: 2951–2956. Available: http://dx.doi.org/10.1016/j.ijhydene.2012.12.037.en
dc.identifier.issn0360-3199en
dc.identifier.doi10.1016/j.ijhydene.2012.12.037en
dc.identifier.urihttp://hdl.handle.net/10754/597612en
dc.description.abstractNickel foam (NF), stainless steel wool (SSW), platinum coated stainless steel mesh (Pt), and molybdenum disulfide coated stainless steel mesh (MoS 2) electrodes have been proposed as catalysts for hydrogen gas production, but previous tests have primarily examined their performance in well buffered solutions. These materials were compared using two-chamber microbial electrolysis cells (MECs), and linear sweep voltammetry (LSV) in unbuffered saline solutions at two different initial pHs (7 and 12). There was generally no appreciable effect of initial pH on production rates or total gas production. NF produced hydrogen gas at a rate of 1.1 m3 H2/m 3·d, which was only slightly less than that using Pt (1.4 m3 H2/m3·d), but larger than that obtained with SSW (0.52 m3 H2/m3·d) or MoS2 (0.67 m3 H2/m3·d). Overall hydrogen gas recoveries with SSW (29.7 ± 0.5 mL), MoS2 (28.6 ± 1.3 mL) and NF (32.4 ± 2 mL) were only slightly less than that of Pt (37.9 ± 0.5 mL). Total energy recoveries, based on the gas produced versus electrical energy input, ranged from 0.75 ± 0.02 for Pt, to 0.55 ± 0.02 for SSW. An LSV analysis showed no effect of pH for NF and Pt, but overpotentials were reduced for MoS2 and SSW by using an initial lower pH. At cathode potentials more negative than -0.85 V (vs Ag/AgCl), NF had lower overpotentials than the MoS2. These results provide the first assessment of these materials under practical conditions of high pH in unbuffered saline catholytes, and position NF as the most promising inexpensive alternative to Pt.en
dc.description.sponsorshipThis work was supported by Award KUS-I1-003-13 from the King Abdullah University of Science and Technology (KAUST).en
dc.publisherElsevier BVen
dc.subjectAlkaline pHen
dc.subjectBufferen
dc.subjectMicrobial electrolysis cellsen
dc.subjectMolybdenum disulfideen
dc.subjectNickel foamen
dc.subjectStainless steel woolen
dc.titleAssessment of four different cathode materials at different initial pHs using unbuffered catholytes in microbial electrolysis cellsen
dc.typeArticleen
dc.identifier.journalInternational Journal of Hydrogen Energyen
dc.contributor.institutionUniversidad Autonoma de Barcelona, Barcelona, Spainen
dc.contributor.institutionPennsylvania State University, State College, United Statesen
kaust.grant.numberKUS-I1-003-13en
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