Corresponding Author

Dong Wang(wangd@iccas.ac.cn)


As an electrochemical energy conversion system, fuel cell has the advantages of high energy conversion efficiency and high cleanliness. Oxygen reduction reaction (ORR), as an important cathode reaction in fuel cells, has received extensive attention. At present, the electrocatalysts are still one of the key materials restricting the further commercialization of fuel cells. The fundamental understanding on the catalytic mechanism of ORR is conducive to the development of electrocatalysts with the enhanced activity and high selectivity. This review aims to summarize the in situ characterization techniques used to study ORR. From this perspective, we first briefly introduce the advantages of various in situ techniques in ORR research, including electrochemical scanning tunneling microscopy, infrared spectroscopy, Raman spectroscopy, X-ray absorption spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy. Then, the applications of various in situ characterization techniques in characterizing of the catalyst morphological evolution and electronic structure as well as the identification of reactants and intermediates in the catalytic process are summarized. Finally, the future development of in situ technology is outlooked.

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oxygen reduction reaction, in situ characterization, electrocatalytic process

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