原位/工况穆斯堡尔谱视角下的铁基氧还原反应电催化剂

doi:10.61558/2993-074X.3578

摘要/Abstract

摘要：

开发经济高效的氧还原反应（ORR）催化剂是一项重大挑战，尤其是在寻找铂等贵金属替代材料的研究中。近年来的显著进展推动电化学研究者利用储量丰富的材料开发高效ORR催化剂，其中铁（Fe）基材料因其优异的ORR催化性能而备受关注。尽管学界已认识到Fe在提升ORR催化活性中的关键作用，但材料属性与催化性能之间的关联仍尚不明确。对于设计无贵金属ORR电催化剂而言，理解氧电催化过程中的动态变化至关重要。穆斯堡尔谱（Mössbauer spectroscopy）在解析催化体系中Fe物种的结构特征方面具有独特优势，能够助力识别活性位点、阐明催化机理。本文通过综述领域内的典型研究案例，阐明了原位/工况⁵⁷Fe 穆斯堡尔谱在各类铁基 ORR 催化材料中的应用，重点揭示了ORR催化的多个核心方面（如活性位点识别、稳定性评估、反应机理理解）。此外，本文还探讨了穆斯堡尔谱技术在该研究领域中的应用机遇与挑战，旨在揭示这一关键研究方向的潜在突破点与改进方向。

关键词: 铁基电催化剂, 原位 / 工况表征, 穆斯堡尔谱, 氧还原反应, 构效关系

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.

Key words: Iron-based electrocatalyst, In-situ/operando analysis, M?ssbauer spectroscopy, Oxygen reduction reaction, Structure-activity relationship

Sumbal Farid, 王军虎. 原位/工况穆斯堡尔谱视角下的铁基氧还原反应电催化剂[J]. 电化学（中英文）, 2026, 32(1): 2506261.

Sumbal Farid, Jun-Hu Wang. Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy[J]. Journal of Electrochemistry, 2026, 32(1): 2506261.

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链接本文: https://electrochem.xmu.edu.cn/CN/10.61558/2993-074X.3578

https://electrochem.xmu.edu.cn/CN/Y2026/V32/I1/2506261

图/表 14

参考文献 91

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#	ORR catalyst	Pyrolysis temperature	Atmosphere	Medium	Mössbauer	Attribution to ORR	Reference
1	FePc-C	420 °C	He/H₂	1 mol·L^-1 NaOH, 0.5 mol·L^-1 H₂SO₄	In-situ	Small FePc crystallites	Scherson et al. 1982
2	FeTPP-Cl/carbon	325-800 °C	Ar	0.5 mol·L^-1 H₂SO₄	In-situ	Only a fraction of Fe-N₄ sites	Bouwkamp-Wijnoltz et al. 2002
3	Fe-N-C	950-1050 °C	Ar+NH₃	-	Ex-situ	FeN₄/C, N-FeN₂₊₂/C sites	Kramm et al. 2014
4	Fe-N-C	900-1050 °C	Ar, NH₃	0.1 mol·L^-1 H₂SO₄	Ex-situ	Porphyrinic FeN₄	Zitolo et al. 2015
5	Fe_0.5-NC	1050 °C	Ar	-	Ex-situ	Surface FeN_xsites	Mineva et al. 2019
6	Fe-NC, Fe-NC-S_0.2, Fe-NC-S_0.4, Fe-NC-S	950 °C	N₂	0.1 mol·L^-1 KOH, 0.1 mol·L^-1 HClO₄	Operando	N-FeN₄C₁₀	Li et al. 2020
7	FeNC_phen, FeNC_ppy, FeNC_porph	800 °C	N₂	0.1 mol·L^-1 H₂SO₄	In-situ	Two different Fe sites	Ni et al. 2021
8	Fe-N-C	950 °C	Ar	0.5 mol·L^-1 H₂SO₄	In-situ	HS-FeN₄C₁₂, LS-FeN₄C₁₀	Li et al. 2021
9	Fe-N-C	1050 °C	N₂	0.1 mol·L^-1 HClO₄	In-situ	FeN₄C₈, FeN₄C₁₂	Xu et al. 2022
10	Fe-N-C	800 °C	N₂	0.1 mol·L^-1 H₂SO₄	Operando	Pyrrolic FeN₄	Ni et al. 2022
11	FeSnNC, FeCoNC	900 °C	N₂	0.1 mol·L^-1 HClO₄	Ex-situ	Fe D1 site	Luo et al. 2023
12	Fe-N_xP_y	900 °C	N₂	0.1 mol·L^-1 KOH	Ex-situ	Fe-N₃P₁	Liu et al. 2024