Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy

Sumbal Farid; Jun-Hu Wang

doi:10.61558/2993-074X.3578

Journal of Electrochemistry ›› 2026, Vol. 32 ›› Issue (1) :2506261 DOI: 10.61558/2993-074X.3578

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Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy

Sumbal Farid ^a^,^b
, Jun-Hu Wang ^a^,^b^,^*

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Abstract

Exploring cost-effective and efficient catalysts for oxygen reduction reaction (ORR) poses a significant challenge, especially in the pursuit of alternatives to precious metals like platinum. Significant advancements have driven electrochemists to develop efficient ORR catalysts using abundant materials, particularly iron (Fe)-based, known for their exceptional performance in ORR. While the crucial function of Fe in boosting ORR catalytic activity is recognized, the connection between material attributes and catalytic performance remains enigmatic. Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts. Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis, facilitating the identification of active sites and the clarification of catalytic mechanisms. By showcasing noteworthy case studies within this review, we demonstrate the application of in-situ/operando ⁵⁷Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis. This sheds light on various aspects of ORR catalysis, such as identifying active sites, assessing stability, and understanding the reaction mechanism. Our inquiry drives towards the opportunities and hurdles associated with Mössbauer spectroscopy, unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm.

Keywords

Iron-based electrocatalyst / In-situ/operando analysis / Mössbauer spectroscopy / Oxygen reduction reaction / Structure-activity relationship

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Sumbal Farid, Jun-Hu Wang. Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy. Journal of Electrochemistry, 2026, 32(1): 2506261 DOI:10.61558/2993-074X.3578

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Conflicts of Interest

The authors declare no conflict of interest.

Data Availability

Data will be made available on request.

Author Contributions

Sumbal Farid: Conceptualization, Writing-original draft; Jun-Hu Wang: Validation, Supervision.

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (22350410386, W2412116, 22375200, U22A202175, 21961142006).

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