1. Strong interactions through the highly polar "Early–Late" metal–metal bonds enable single–atom catalysts good durability and superior bifunctional ORR/OER activity.
- Author
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Yan, Tingyu, Lang, Simone, Liu, Song, Wang, Siyao, Lin, Shiru, Cai, Qinghai, and Zhao, Jingxiang
- Subjects
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METAL-metal bonds , *ELECTROCATALYSIS , *CATALYSTS , *CATALYTIC activity , *DURABILITY , *ENERGY conversion - Abstract
[Display omitted] Simultaneously enhancing the durability and catalytic performance of metal-nitrogen-carbon (M−N x −C) single–atom catalysts is critical to boost oxygen electrocatalysis for energy conversion and storage, yet it remains a grand challenge. Herein, through the combination of early and late metals, we proposed to enhance the stability and tune the catalytic activity of M−N x −C SACs in oxygen electrocatalysis by their strong interaction with the M 2 ′C–type MXene substrate. Our density functional theory (DFT) computations revealed that the strong interaction between "early-late" metal–metal bonds significantly improves thermal and electrochemical stability. Due to considerable charge transfer and shift of the d-band center, the electronic properties of these SACs can be extensively modified, thereby optimizing their adsorption strength with oxygenated intermediates and achieving eight promising bifunctional catalysts for ORR/OER with low overpotentials. More importantly, the constant-potential analysis demonstrated the excellent bifunctional activity of SACs supported on MXene substrate across a broad pH range, especially in strongly alkaline media with record-low overpotentials. Further machine learning analysis shows that the d-band center, the charge of the active site, and the work function of the formed heterojunctions are critical to revealing the ORR/OER activity origin. Our results underscore the vast potential of strong interactions between different metal species in enhancing the durability and catalytic performance of SACs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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