New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells
Autor(a) principal: | |
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Data de Publicação: | 2018 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1016/j.apcatb.2017.10.037 http://hdl.handle.net/11449/170348 |
Resumo: | Ethanol oxidation reaction (EOR) on Pd2Ru/C and Pd/C catalysts in alkaline media is studied comprehensively by cyclic voltammetry, chronoamperometry, in situ FTIR, single fuel cell test and electrochemical impedance spectroscopy measurements. The results show that, as compared to Pd/C, Pd2Ru/C favors acetaldehyde formation and hinders its oxidation. Based on X-ray absorption data, which evidence that Ru promotes a larger electronic vacancy of the Pd 4d band, it is expected that the formation of adsorbed ethoxy is favored on Pd2Ru/C and followed by its oxidation to acetaldehyde facilitated by oxygenated species provided by Ru. In contrast, acetaldehyde oxidation is more difficult on Pd2Ru/C than on Pd/C likely because the adsorption energy of the reactive species is increased. We also show that the performance of Pd2Ru/C anode in alkaline direct ethanol fuel cell (ADEFC) is initially better but degrades much more rapidly than that with Pd/C anode under the same test conditions. The degradation is demonstrated to result from the accumulation of large amounts of acetaldehyde, which in alkaline media forms dimers by the aldol condensation reaction. The dimers tend to be responsible for blocking the active sites for further ethanol oxidation. This comprehensive study provides new understandings of the roles of Ru in Pd2Ru/C for EOR in alkaline media, unveils the causes of the performance degradation of fuel cells with Pd2Ru/C and demonstrates that initial good performances are not necessarily a valid criterion for selecting appropriate anode catalysts for ADEFC applications. |
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New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cellsAlkaline direct alcohol fuel cellsCatalyst deactivationEthanol electro-oxidationEthanol oxidation reaction (EOR) on Pd2Ru/C and Pd/C catalysts in alkaline media is studied comprehensively by cyclic voltammetry, chronoamperometry, in situ FTIR, single fuel cell test and electrochemical impedance spectroscopy measurements. The results show that, as compared to Pd/C, Pd2Ru/C favors acetaldehyde formation and hinders its oxidation. Based on X-ray absorption data, which evidence that Ru promotes a larger electronic vacancy of the Pd 4d band, it is expected that the formation of adsorbed ethoxy is favored on Pd2Ru/C and followed by its oxidation to acetaldehyde facilitated by oxygenated species provided by Ru. In contrast, acetaldehyde oxidation is more difficult on Pd2Ru/C than on Pd/C likely because the adsorption energy of the reactive species is increased. We also show that the performance of Pd2Ru/C anode in alkaline direct ethanol fuel cell (ADEFC) is initially better but degrades much more rapidly than that with Pd/C anode under the same test conditions. The degradation is demonstrated to result from the accumulation of large amounts of acetaldehyde, which in alkaline media forms dimers by the aldol condensation reaction. The dimers tend to be responsible for blocking the active sites for further ethanol oxidation. This comprehensive study provides new understandings of the roles of Ru in Pd2Ru/C for EOR in alkaline media, unveils the causes of the performance degradation of fuel cells with Pd2Ru/C and demonstrates that initial good performances are not necessarily a valid criterion for selecting appropriate anode catalysts for ADEFC applications.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)National Natural Science Foundation of ChinaRichard G. Lugar Center for Renewable Energy Indiana University Purdue UniversityDepartment of Chemical Engineering University of ToledoState Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering School of Energy Research Xiamen UniversityUniversidade Estadual Paulista (UNESP) Instituto de QuímicaUniversidade Estadual Paulista (UNESP) Instituto de QuímicaFAPESP: 2013/50206-4FAPESP: 2014/12255-6National Natural Science Foundation of China: 21361140374Indiana University Purdue UniversityUniversity of ToledoXiamen UniversityUniversidade Estadual Paulista (Unesp)Guo, JunsongChen, RongrongZhu, Fu-ChunSun, Shi-GangVillullas, Hebe M. [UNESP]2018-12-11T16:50:23Z2018-12-11T16:50:23Z2018-05-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article602-611application/pdfhttp://dx.doi.org/10.1016/j.apcatb.2017.10.037Applied Catalysis B: Environmental, v. 224, p. 602-611.0926-3373http://hdl.handle.net/11449/17034810.1016/j.apcatb.2017.10.0372-s2.0-850328939762-s2.0-85032893976.pdfScopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengApplied Catalysis B: Environmental3,152info:eu-repo/semantics/openAccess2023-12-15T06:20:56Zoai:repositorio.unesp.br:11449/170348Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462023-12-15T06:20:56Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
title |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
spellingShingle |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells Guo, Junsong Alkaline direct alcohol fuel cells Catalyst deactivation Ethanol electro-oxidation |
title_short |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
title_full |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
title_fullStr |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
title_full_unstemmed |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
title_sort |
New understandings of ethanol oxidation reaction mechanism on Pd/C and Pd2Ru/C catalysts in alkaline direct ethanol fuel cells |
author |
Guo, Junsong |
author_facet |
Guo, Junsong Chen, Rongrong Zhu, Fu-Chun Sun, Shi-Gang Villullas, Hebe M. [UNESP] |
author_role |
author |
author2 |
Chen, Rongrong Zhu, Fu-Chun Sun, Shi-Gang Villullas, Hebe M. [UNESP] |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Indiana University Purdue University University of Toledo Xiamen University Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Guo, Junsong Chen, Rongrong Zhu, Fu-Chun Sun, Shi-Gang Villullas, Hebe M. [UNESP] |
dc.subject.por.fl_str_mv |
Alkaline direct alcohol fuel cells Catalyst deactivation Ethanol electro-oxidation |
topic |
Alkaline direct alcohol fuel cells Catalyst deactivation Ethanol electro-oxidation |
description |
Ethanol oxidation reaction (EOR) on Pd2Ru/C and Pd/C catalysts in alkaline media is studied comprehensively by cyclic voltammetry, chronoamperometry, in situ FTIR, single fuel cell test and electrochemical impedance spectroscopy measurements. The results show that, as compared to Pd/C, Pd2Ru/C favors acetaldehyde formation and hinders its oxidation. Based on X-ray absorption data, which evidence that Ru promotes a larger electronic vacancy of the Pd 4d band, it is expected that the formation of adsorbed ethoxy is favored on Pd2Ru/C and followed by its oxidation to acetaldehyde facilitated by oxygenated species provided by Ru. In contrast, acetaldehyde oxidation is more difficult on Pd2Ru/C than on Pd/C likely because the adsorption energy of the reactive species is increased. We also show that the performance of Pd2Ru/C anode in alkaline direct ethanol fuel cell (ADEFC) is initially better but degrades much more rapidly than that with Pd/C anode under the same test conditions. The degradation is demonstrated to result from the accumulation of large amounts of acetaldehyde, which in alkaline media forms dimers by the aldol condensation reaction. The dimers tend to be responsible for blocking the active sites for further ethanol oxidation. This comprehensive study provides new understandings of the roles of Ru in Pd2Ru/C for EOR in alkaline media, unveils the causes of the performance degradation of fuel cells with Pd2Ru/C and demonstrates that initial good performances are not necessarily a valid criterion for selecting appropriate anode catalysts for ADEFC applications. |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018-12-11T16:50:23Z 2018-12-11T16:50:23Z 2018-05-01 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1016/j.apcatb.2017.10.037 Applied Catalysis B: Environmental, v. 224, p. 602-611. 0926-3373 http://hdl.handle.net/11449/170348 10.1016/j.apcatb.2017.10.037 2-s2.0-85032893976 2-s2.0-85032893976.pdf |
url |
http://dx.doi.org/10.1016/j.apcatb.2017.10.037 http://hdl.handle.net/11449/170348 |
identifier_str_mv |
Applied Catalysis B: Environmental, v. 224, p. 602-611. 0926-3373 10.1016/j.apcatb.2017.10.037 2-s2.0-85032893976 2-s2.0-85032893976.pdf |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Applied Catalysis B: Environmental 3,152 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
602-611 application/pdf |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1799965298439225344 |