| Autor: |
Hötger D; Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany. r.gutzler@fkf.mpg.de., Etzkorn M, Morchutt C, Wurster B, Dreiser J, Stepanow S, Grumelli D, Gutzler R, Kern K |
| Jazyk: |
angličtina |
| Zdroj: |
Physical chemistry chemical physics : PCCP [Phys Chem Chem Phys] 2019 Jan 30; Vol. 21 (5), pp. 2587-2594. |
| DOI: |
10.1039/c8cp07463a |
| Abstrakt: |
Transition metal atoms stabilised by organic ligands or as oxides exhibit promising catalytic activity for the electrocatalytic reduction and evolution of oxygen. Built-up from earth-abundant elements, they offer affordable alternatives to precious-metal based catalysts for application in fuel cells and electrolysers. For the understanding of a catalyst's activity, insight into its structure on the atomic scale is of highest importance, yet commonly challenging to experimentally access. Here, the structural integrity of a bimetallic iron tetrapyridylporphyrin with co-adsorbed cobalt electrocatalyst on Au(111) is investigated using scanning tunneling microscopy and X-ray absorption spectroscopy. Topographic and spectroscopic characterization reveals structural changes of the molecular coordination network after oxygen reduction, and its decomposition and transformation into catalytically active Co/Fe (oxyhydr)oxide during oxygen evolution. The data establishes a structure-property relationship for the catalyst as a function of electrochemical potential and, in addition, highlights how the reaction direction of electrochemical interconversion between molecular oxygen and hydroxyl anions can have very different effects on the catalyst's structure. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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