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The key challenge for scalable production of hydrogen from water lies in the rational design and preparation of high-performance and earth-abundant electrocatalysts to replace precious metal Pt and IrO2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Although atomic M-N-C materials have been extensively studied in heterogeneous catalysis field, the insufficient antioxidant capacity of carbonous substrates hinders their practical application in OER. Developing highly active and stable OER electrocatalysts is the key for electrochemical water splitting. This review presents feasible design strategies for fabricating carbon-free single-site catalysts and their applications in HER/OER and overall water splitting. The constitutive relationships between structure, composition, and catalytic performance for HER and OER are detailly discussed, providing ponderable insights into rationally constructing high-performance HER and OER electrocatalysts. The perspectives on the challenges and future research orientations in single-site catalysts for electrochemical water splitting are suggested.

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Recent progress and prospect of carbon-free single-site catalysts for the hydrogen and oxygen evolution reactions

Show Author's information Jingqi Guan( )Xue BaiTianmi Tang
Institute of Physical Chemistry, College of ChemistryJilin University, 2519 Jiefang RoadChangchun130021China


The key challenge for scalable production of hydrogen from water lies in the rational design and preparation of high-performance and earth-abundant electrocatalysts to replace precious metal Pt and IrO2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Although atomic M-N-C materials have been extensively studied in heterogeneous catalysis field, the insufficient antioxidant capacity of carbonous substrates hinders their practical application in OER. Developing highly active and stable OER electrocatalysts is the key for electrochemical water splitting. This review presents feasible design strategies for fabricating carbon-free single-site catalysts and their applications in HER/OER and overall water splitting. The constitutive relationships between structure, composition, and catalytic performance for HER and OER are detailly discussed, providing ponderable insights into rationally constructing high-performance HER and OER electrocatalysts. The perspectives on the challenges and future research orientations in single-site catalysts for electrochemical water splitting are suggested.

Keywords: single-atom catalyst, oxygen evolution reaction, water splitting, hydrogen evolution reaction, single-site catalyst



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Publication history

Publication history

Received: 13 May 2021
Revised: 09 June 2021
Accepted: 14 June 2021
Published: 07 August 2021
Issue date: February 2022


© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021



This work was supported by the National Natural Science Foundation of China (No. 22075099), and Natural Science Foundation of Jilin Province (No. 20180101291JC).