Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ
Three ferrite based perovskites were investigated as cathodes for the electrochemical reduction of oxygen and nitric oxide, using cone-shaped electrodes and cyclic voltammetry. The ferrites investigated were LaFeO3, La0.85Sr0.15FeO3−δ and La0.5Sr0.5FeO3−δ. Especially the effect of anodic pre-treatme...
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| Format: | Article |
| Language: | English |
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The Electrochemical Society of Japan
2020-05-01
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| Series: | Electrochemistry |
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| Online Access: | https://www.jstage.jst.go.jp/article/electrochemistry/88/3/88_19-00069/_pdf/-char/en |
| _version_ | 1797970542677983232 |
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| author | K. Kammer HANSEN |
| author_facet | K. Kammer HANSEN |
| author_sort | K. Kammer HANSEN |
| collection | DOAJ |
| description | Three ferrite based perovskites were investigated as cathodes for the electrochemical reduction of oxygen and nitric oxide, using cone-shaped electrodes and cyclic voltammetry. The ferrites investigated were LaFeO3, La0.85Sr0.15FeO3−δ and La0.5Sr0.5FeO3−δ. Especially the effect of anodic pre-treatment of the electrodes was investigated. It was shown that the ferrite based electrodes are better at reducing nitric oxide than oxygen in the temperature range 200 to 400°C. The ability of the ferrites to reduce oxygen depends mainly on the amount of Fe(III) and oxide anion vacancies, leading to the highest activity towards the reduction of oxygen for the intermediate compound La0.85Sr0.15FeO3−δ in the investigated temperature range. All the electrodes were either activated or de-activated when polarized at 0.4 vs. air, before recording the voltammograms, depending on temperature and gas atmosphere. This was attributed to annihilation of oxide ion vacancies, strontium segregation to the surface of the electrodes and perhaps formation of Fe(IV). The effect of water vapor was also studied. It had a slightly deactivating effect on the activity in the nitric oxide containing atmosphere, the effect being highest at the lowest temperatures. |
| first_indexed | 2024-04-11T03:19:29Z |
| format | Article |
| id | doaj.art-8847572fac1e416ebe6d2a47b416e7cd |
| institution | Directory Open Access Journal |
| issn | 2186-2451 |
| language | English |
| last_indexed | 2024-04-11T03:19:29Z |
| publishDate | 2020-05-01 |
| publisher | The Electrochemical Society of Japan |
| record_format | Article |
| series | Electrochemistry |
| spelling | doaj.art-8847572fac1e416ebe6d2a47b416e7cd2023-01-02T09:33:51ZengThe Electrochemical Society of JapanElectrochemistry2186-24512020-05-0188314615010.5796/electrochemistry.19-00069electrochemistryActivation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δK. Kammer HANSEN0Department of Energy Conversion and Storage, Technical University of DenmarkThree ferrite based perovskites were investigated as cathodes for the electrochemical reduction of oxygen and nitric oxide, using cone-shaped electrodes and cyclic voltammetry. The ferrites investigated were LaFeO3, La0.85Sr0.15FeO3−δ and La0.5Sr0.5FeO3−δ. Especially the effect of anodic pre-treatment of the electrodes was investigated. It was shown that the ferrite based electrodes are better at reducing nitric oxide than oxygen in the temperature range 200 to 400°C. The ability of the ferrites to reduce oxygen depends mainly on the amount of Fe(III) and oxide anion vacancies, leading to the highest activity towards the reduction of oxygen for the intermediate compound La0.85Sr0.15FeO3−δ in the investigated temperature range. All the electrodes were either activated or de-activated when polarized at 0.4 vs. air, before recording the voltammograms, depending on temperature and gas atmosphere. This was attributed to annihilation of oxide ion vacancies, strontium segregation to the surface of the electrodes and perhaps formation of Fe(IV). The effect of water vapor was also studied. It had a slightly deactivating effect on the activity in the nitric oxide containing atmosphere, the effect being highest at the lowest temperatures.https://www.jstage.jst.go.jp/article/electrochemistry/88/3/88_19-00069/_pdf/-char/ennitric oxideoxygenlsf |
| spellingShingle | K. Kammer HANSEN Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ Electrochemistry nitric oxide oxygen lsf |
| title | Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ |
| title_full | Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ |
| title_fullStr | Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ |
| title_full_unstemmed | Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ |
| title_short | Activation/Deactivation Phenomena’s in the Electrochemical Reduction of O2 and NO on La1−xSrxFeO3−δ |
| title_sort | activation deactivation phenomena s in the electrochemical reduction of o2 and no on la1 xsrxfeo3 δ |
| topic | nitric oxide oxygen lsf |
| url | https://www.jstage.jst.go.jp/article/electrochemistry/88/3/88_19-00069/_pdf/-char/en |
| work_keys_str_mv | AT kkammerhansen activationdeactivationphenomenasintheelectrochemicalreductionofo2andnoonla1xsrxfeo3d |