Jafar Hussain Shah, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Qi-Xian Xie, 2. Institute of Photoelectronic Thin Film Devices and Technology, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Renewable Energy Conversion and Storage Center, Nankai University, Tianjin 300350, China;
Zhi-Chong Kuang, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Ri-Le Ge, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Wen-Hui Zhou, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Duo-Rong Liu, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Alexandre I. Rykov, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Xu-Ning Li, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
Jing-Shan Luo, 2. Institute of Photoelectronic Thin Film Devices and Technology, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Renewable Energy Conversion and Storage Center, Nankai University, Tianjin 300350, China;
Jun-Hu Wang, 1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;Follow

Corresponding Author

Jun-Hu Wang(wangjh@dicp.ac.cn)


The development of highly efficient and cost-effective electrocatalysts for the sluggish oxygen evolution reaction (OER) remains a significant barrier to establish effective utilization of renewable energy storage systems and water splitting to produce clean fuel. The current status of the research in developing OER catalysts shows that NiFe-based oxygen evolution catalysts (OECs) have been proven as excellent and remarkable candidates for this purpose. But it is critically important to understand the factors that influence their activity and underlying mechanism for the development of state-of-the-art OER catalysts. Therefore, the development of in-situ/operando characterizations is urgently required to detect key intermediates along with active sites and phases responsible for OER. 57Fe Mössbauer spectroscopy is one of the appropriate and suitable techniques for determining the phase structure of catalysts under their electrochemical working conditions, identifying the active sites, clarifying the catalytic mechanisms, and determining the relationship between catalytic activity and the coordination structure of catalysts. In this tutorial review, we have discussed the current status of research on NiFe-based catalysts with particular attention to introduce in detail the knowhow about the development and utilization of in-situ/operando57Fe Mössbauer-electrochemical spectroscopy for the study of OER mechanism. A brief overview using NiFe-(oxy)hydroxide catalysts, derived from ordered porous metal-organic framework (MOF) material NiFe-PBAs (Prussian blue analogues), as a typical model study case for the OER electrocatalyst and self-designed in-situ/operando57Fe Mössbauer-electrochemical instrument, has been provided for the better understanding of readers. Moreover, using in-situ/operando57Fe Mössbauer spectroscopy, the crucial role of Fe species during OER reaction has been explained very well.

Graphical Abstract


oxygen evolution reaction, NiFe-(oxy)hydroxide electrocatalyst, NiFe Prussian blue analogue, in-situ/operando57Fe Mössbauer spectroscopy, key intermediate detection

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