Ionic Liquid Enhanced Proton Transfer for Neutral Oxygen Evolution Reaction

Authors

Ming-Xing Chen, Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, China
Nian Liu, Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, China
Zi-He Dua, Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, China
Jing Qi, Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, ChinaFollow
Rui Cao, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710119, ChinaFollow

Corresponding Author

Jing Qi (qijing2020@htu.edu.cn);
Rui Cao (ruicao@snnu.edu.cn)

Abstract

The development of highly active catalyst in pH-neutral media for oxygen evolution reaction (OER) is critical in the field of renewable energy storage and conversion. Nevertheless, the slow kinetics of proton-coupled electron transfer (PCET) hinders the overall OER efficiency. Herein, we report an ionic liquid (IL) modified CoSn(OH)⁶ nanocubes (denoted as CoSn( OH)⁶-IL), which could be prepared through a facile strategy. The modified IL would not change the structural characteristics of CoSn(OH)⁶, but could effectively regulate the local proton activity near the active sites. The CoSn(OH)⁶-IL exhibited higher intrinsic OER performances than the pristine CoSn(OH)⁶ in neutral media. For example, the current density of CoSn( OH)⁶-IL at 1.8 V versus reversible hydrogen electrode (RHE) was about 4 times higher than that of CoSn(OH)⁶. According to the pH-dependent kinetic investigations, operando electrochemical impedance spectroscopic, chemical probe tests, and deuterium kinetic isotope effects, the interfacial layer of IL could be utilized as a proton transfer mediator to promote the proton transfer, which enhances the surface coverage of OER intermediates and reduces the activation barrier. Consequently, the sluggish OER kinetics would be efficiently accelerated. This study provides a facile and effective strategy to facilitate the PCET processes and is beneficial to guide the rational design of OER electrocatalysts.

Graphical Abstract

Keywords

Electrocatalysis, Oxygen evolution reaction, Ionic liquid, Proton transfer, CoSn(OH)6 nanocube

DOI Link

https://doi.org/10.61558/2993-074X.3549

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Publication Date

2025-07-28

Online Available Date

2025-05-16

Revised Date

2025-04-30

Received Date

2025-03-25

Recommended Citation

Ming-Xing Chen, Nian Liu, Zi-He Dua, Jing Qi, Rui Cao. Ionic Liquid Enhanced Proton Transfer for Neutral Oxygen Evolution Reaction[J]. Journal of Electrochemistry, 2025 , 31(7): 2515001.
DOI: 10.61558/2993-074X.3549
Available at: https://jelectrochem.xmu.edu.cn/journal/vol31/iss7/3