Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys
Proton exchange membrane fuel cells and direct alcohol fuel cells have been extensively studied over the last three decades or so. They have emerged as potential systems to power portable applications, providing clean energy, and offering good commercial viability. Ethanol is considered one of the m...
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| Format: | Article |
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MDPI AG
2020-04-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/13/7/1658 |
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| author | D.M.F. Santos J.R.B. Lourenço D. Macciò A. Saccone C.A.C. Sequeira J.L. Figueiredo |
| author_facet | D.M.F. Santos J.R.B. Lourenço D. Macciò A. Saccone C.A.C. Sequeira J.L. Figueiredo |
| author_sort | D.M.F. Santos |
| collection | DOAJ |
| description | Proton exchange membrane fuel cells and direct alcohol fuel cells have been extensively studied over the last three decades or so. They have emerged as potential systems to power portable applications, providing clean energy, and offering good commercial viability. Ethanol is considered one of the most interesting fuels in this field. Herein, platinum-rare earth (Pt-RE) binary alloys (RE = Ce, Sm, Ho, Dy, nominal composition 50 at.% Pt) were produced and studied as anodes for ethanol oxidation reaction (EOR) in alkaline medium. A Pt-Dy alloy with nominal composition 40 at.% Pt was also tested. Their electrocatalytic performance was evaluated by voltammetric and chronoamperometric measurements in 2 M NaOH solution with different ethanol concentrations (0.2–0.8 M) in the 25–45 °C temperature range. Several EOR kinetic parameters were determined for the Pt-RE alloys, namely the charge transfer and diffusion coefficients, and the number of exchanged electrons. Charge transfer coefficients ranging from 0.60 to 0.69 and n values as high as 0.7 were obtained for the Pt<sub>0.5</sub>Sm<sub>0.5</sub> electrode. The EOR reaction order at the Pt-RE alloys was found to vary between 0.4 and 0.9. The Pt-RE electrodes displayed superior performance for EOR than bare Pt, with Pt<sub>0.5</sub>Sm<sub>0.5</sub> exhibiting the highest electrocatalytic activity. The improved electrocatalytic activity in all of the evaluated Pt-RE binary alloys suggests a strategy for the solution of the existing anode issues due to the structure-sensitive EOR. |
| first_indexed | 2024-03-10T20:42:36Z |
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| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T20:42:36Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-1711798097114e8592f890dafbd3fb032023-11-19T20:32:57ZengMDPI AGEnergies1996-10732020-04-01137165810.3390/en13071658Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary AlloysD.M.F. Santos0J.R.B. Lourenço1D. Macciò2A. Saccone3C.A.C. Sequeira4J.L. Figueiredo5CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, PortugalCeFEMA, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, PortugalDipartimento di Chímica e Chímica Industriale, Universitá di Genova, I-16146 Genova, ItalyDipartimento di Chímica e Chímica Industriale, Universitá di Genova, I-16146 Genova, ItalyCeFEMA, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, PortugalLaboratory of Catalysis and Materials, LSRE-LCM, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto, PortugalProton exchange membrane fuel cells and direct alcohol fuel cells have been extensively studied over the last three decades or so. They have emerged as potential systems to power portable applications, providing clean energy, and offering good commercial viability. Ethanol is considered one of the most interesting fuels in this field. Herein, platinum-rare earth (Pt-RE) binary alloys (RE = Ce, Sm, Ho, Dy, nominal composition 50 at.% Pt) were produced and studied as anodes for ethanol oxidation reaction (EOR) in alkaline medium. A Pt-Dy alloy with nominal composition 40 at.% Pt was also tested. Their electrocatalytic performance was evaluated by voltammetric and chronoamperometric measurements in 2 M NaOH solution with different ethanol concentrations (0.2–0.8 M) in the 25–45 °C temperature range. Several EOR kinetic parameters were determined for the Pt-RE alloys, namely the charge transfer and diffusion coefficients, and the number of exchanged electrons. Charge transfer coefficients ranging from 0.60 to 0.69 and n values as high as 0.7 were obtained for the Pt<sub>0.5</sub>Sm<sub>0.5</sub> electrode. The EOR reaction order at the Pt-RE alloys was found to vary between 0.4 and 0.9. The Pt-RE electrodes displayed superior performance for EOR than bare Pt, with Pt<sub>0.5</sub>Sm<sub>0.5</sub> exhibiting the highest electrocatalytic activity. The improved electrocatalytic activity in all of the evaluated Pt-RE binary alloys suggests a strategy for the solution of the existing anode issues due to the structure-sensitive EOR.https://www.mdpi.com/1996-1073/13/7/1658ethanol electrooxidationPt-RE alloysdirect ethanol fuel cellelectrocatalysis |
| spellingShingle | D.M.F. Santos J.R.B. Lourenço D. Macciò A. Saccone C.A.C. Sequeira J.L. Figueiredo Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys Energies ethanol electrooxidation Pt-RE alloys direct ethanol fuel cell electrocatalysis |
| title | Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys |
| title_full | Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys |
| title_fullStr | Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys |
| title_full_unstemmed | Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys |
| title_short | Ethanol Electrooxidation at Platinum-Rare Earth (RE = Ce, Sm, Ho, Dy) Binary Alloys |
| title_sort | ethanol electrooxidation at platinum rare earth re ce sm ho dy binary alloys |
| topic | ethanol electrooxidation Pt-RE alloys direct ethanol fuel cell electrocatalysis |
| url | https://www.mdpi.com/1996-1073/13/7/1658 |
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