Operando X‐Ray Absorption Spectroscopy Shows Iron Oxidation Is Concurrent with Oxygen Evolution in Cobalt–Iron (Oxy)hydroxide Electrocatalysts
| Autor: | Shannon W. Boettcher, Maytal Caspary Toroker, Lisa J. Enman, Meir Haim Dahan, Michaela Burke Stevens, Michael R. Nellist |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
X-ray absorption spectroscopy
Absorption spectroscopy Chemistry Inorganic chemistry Oxygen evolution chemistry.chemical_element General Medicine 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Heterogeneous catalysis 01 natural sciences Catalysis 0104 chemical sciences Nickel chemistry.chemical_compound Hydroxide 0210 nano-technology Cobalt |
| Zdroj: | Angewandte Chemie International Edition. 57:12840-12844 |
| ISSN: | 1521-3773 1433-7851 |
| DOI: | 10.1002/anie.201808818 |
| Popis: | Iron cations are essential for the high activity of nickel and cobalt-based (oxy)hydroxides for the oxygen evolution reaction, but the role of iron in the catalytic mechanism remains under active investigation. Operando X-ray absorption spectroscopy and density functional theory calculations are used to demonstrate partial Fe oxidation and a shortening of the Fe-O bond length during oxygen evolution on Co(Fe)Ox Hy . Cobalt oxidation during oxygen evolution is only observed in the absence of iron. These results demonstrate a different mechanism for water oxidation in the presence and absence of iron and support the hypothesis that oxidized iron species are involved in water-oxidation catalysis on Co(Fe)Ox Hy . |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text