Back to Search Start Over

Operando tracking of oxidation-state changes by coupling electrochemistry with time-resolved X-ray absorption spectroscopy demonstrated for water oxidation by a cobalt-based catalyst film

Authors :
Pasquini, Chiara
Liu, Si
Chernev, Petko
Gonzalez-Flores, Diego
Mohammadi, Mohammad Reza
Kubella, Paul
Jiang, Shan
Loos, Stefan
Klingan, Katharina
Sikolenko, Vadim
Mebs, Stefan
Haumann, Michael
Beyer, Paul
D'Amario, Luca
Smith, Rodney D. L.
Zaharieva, Ivelina
Dau, Holger
Pasquini, Chiara
Liu, Si
Chernev, Petko
Gonzalez-Flores, Diego
Mohammadi, Mohammad Reza
Kubella, Paul
Jiang, Shan
Loos, Stefan
Klingan, Katharina
Sikolenko, Vadim
Mebs, Stefan
Haumann, Michael
Beyer, Paul
D'Amario, Luca
Smith, Rodney D. L.
Zaharieva, Ivelina
Dau, Holger
Publication Year :
2021

Abstract

Transition metal oxides are promising electrocatalysts for water oxidation, i.e., the oxygen evolution reaction (OER), which is critical in electrochemical production of non-fossil fuels. The involvement of oxidation state changes of the metal in OER electrocatalysis is increasingly recognized in the literature. Tracing these oxidation states under operation conditions could provide relevant information for performance optimization and development of durable catalysts, but further methodical developments are needed. Here, we propose a strategy to use single-energy X-ray absorption spectroscopy for monitoring metal oxidation-state changes during OER operation with millisecond time resolution. The procedure to obtain time-resolved oxidation state values, using two calibration curves, is explained in detail. We demonstrate the significance of this approach as well as possible sources of data misinterpretation. We conclude that the combination of X-ray absorption spectroscopy with electrochemical techniques allows us to investigate the kinetics of redox transitions and to distinguish the catalytic current from the redox current. Tracking of the oxidation state changes of Co ions in electrodeposited oxide films during cyclic voltammetry in neutral pH electrolyte serves as a proof of principle.

Details

Database :
OAIster
Notes :
application/pdf, English
Publication Type :
Electronic Resource
Accession number :
edsoai.on1312846709
Document Type :
Electronic Resource
Full Text :
https://doi.org/10.1007.s00216-021-03515-0