Abstract
The proton-coupled electron transfer (PCET) kinetics plays a critical role in governing the CO2-to-formate conversion efficiency during CO2 eletroreduction reaction. While alkali metal cations are known to influence the reaction pathway, elucidating how trace doping modifies the catalytic sites remains a key challenge. Here we show that incorporating Li into bismuth oxycarbonate (BOC-Li) induces structural modifications that optimize the PCET process at bismuth-active sites, thereby boosting CO2-to-formate conversion. By employing dual-isotope (2H/13C) operando nuclear magnetic resonance (NMR) to track the formation of 1H13COO−/2H13COO−, combined with kinetic isotope effect, Tafel analysis and in situ attenuated total reflection surface-enhanced infrared absorption …
Abstract
The proton-coupled electron transfer (PCET) kinetics plays a critical role in governing the CO2-to-formate conversion efficiency during CO2 eletroreduction reaction. While alkali metal cations are known to influence the reaction pathway, elucidating how trace doping modifies the catalytic sites remains a key challenge. Here we show that incorporating Li into bismuth oxycarbonate (BOC-Li) induces structural modifications that optimize the PCET process at bismuth-active sites, thereby boosting CO2-to-formate conversion. By employing dual-isotope (2H/13C) operando nuclear magnetic resonance (NMR) to track the formation of 1H13COO−/2H13COO−, combined with kinetic isotope effect, Tafel analysis and in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy, we observe a more efficient proton-electron transfer pathway. Density functional theory (DFT) calculations suggest that Li doping is associated with enhanced activity of Bi sites, potentially strengthening H2O/CO2 adsorption and reducing the O–H activation energy. Collectively, this work highlights alkali doping as a promising strategy for structurally engineering catalytic sites to improve PCET kinetics.
Data availability
The data generated in this study are provided in the Supplementary Information/Source Data file. Key structural data used in the DFT calculations in this study are provided in Supplementary Data 1. Source data are provided with this paper.
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Acknowledgements
This project was supported by Shanghai Municipal Science and Technology Commission(Grant No.YDZX20243100003001001), National Key Research and Development Program of China (2021YFA1500700), the National Natural Science Foundation of China (grant nos. 22572052, 22274052, 22072045, and 21574043), the Science and Technology Commission of Shanghai Municipality (25ZR1402129 and 25DZ3000302), the International (Regional) Cooperation and Exchange Projects of the National Natural Science Foundation of China (51920105003), the Science and Technology Commission of Shanghai Municipality (21DZ1207101), and the Microscale Magnetic Resonance Platform of ECNU.
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Author notes
These authors contributed equally: Yingli Shi, Ying Liu.
Authors and Affiliations
Physics Department & Shanghai Key Laboratory of Magnetic Resonance, School of Physics, Institute of Magnetic Resonance and Molecular Imaging in Medicine, East China Normal University, Shanghai, PR China
Yingli Shi, Hongchun Dong, Gaocheng Fu, Hang Zhou, Xue-Lu Wang & Ye-Feng Yao 1.
State Key Laboratory of Green Chemical Engineering and Industrial Catalysis, Centre for Computational Chemistry and Research Institute of Industrial Catalysis, East China University of Science and Technology, Shanghai, PR China
Ying Liu & Haifeng Wang
Authors
- Yingli Shi
- Ying Liu
- Hongchun Dong
- Gaocheng Fu
- Hang Zhou
- Haifeng Wang
- Xue-Lu Wang
- Ye-Feng Yao
Contributions
X.-L.W. conceived and designed the project. Y.S. conducted experimental work, while Y.L. carried out computational simulations. H.D., G.F., and H.Z. assisted with NMR experimentation and data analysis. Results were collaboratively analyzed by Y.S., Y.L., X.-L.W., H.W., and Y.-F.Y. The manuscript was drafted by Y.S., Y.L., X.-L.W., H.W., and Y.-F.Y., with critical revisions from all authors.
Corresponding authors
Correspondence to Haifeng Wang, Xue-Lu Wang or Ye-Feng Yao.
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Shi, Y., Liu, Y., Dong, H. et al. Operando nuclear magnetic resonance decodes alkali-tuned proton-electron relay boosting CO2-to-formate conversion. Nat Commun (2026). https://doi.org/10.1038/s41467-026-68604-z
Received: 06 June 2025
Accepted: 12 January 2026
Published: 20 January 2026
DOI: https://doi.org/10.1038/s41467-026-68604-z