Surface interrogation scanning electrochemical microscopy (SI‐SECM) of two electrodeposited manganese‐based electrocatalysts, amorphous MnOxand perovskite CaMnO3, was used to investigate the manganese oxidation state relating to the oxygen evolution reaction (OER) under neutral conditions. The results indicate the amounts of MnIIIand MnIVspecies in MnOxand CaMnO3depend on potential. A MnVspecies was identified in both structures during the OER. Time‐delay titration of MnVfurther revealed that MnOxproduced two types of active sites with different OER reaction rates:
Surface interrogation scanning electrochemical microscopy (SI‐SECM) of two electrodeposited manganese‐based electrocatalysts, amorphous MnOxand perovskite CaMnO3, was used to investigate the manganese oxidation state relating to the oxygen evolution reaction (OER) under neutral conditions. The results indicate the amounts of MnIIIand MnIVspecies in MnOxand CaMnO3depend on potential. A MnVspecies was identified in both structures during the OER. Time‐delay titration of MnVfurther revealed that MnOxproduced two types of active sites with different OER reaction rates:
- NSF-PAR ID:
- 10201131
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 133
- Issue:
- 2
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 807-812
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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