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Published May 9, 2025 | Published
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Electrifying amine carbon capture with robust redox-tunable acids

Li, Xing1, 2 ORCID icon
Musgrave, Charles B.3
Liu, Andong1
Meng, Junyang1 ORCID icon
Zhang, Jihan1
Goddard, William A., III3 ORCID icon
Liu, Yayuan1 ORCID icon
  • 1. ROR icon Johns Hopkins University
  • 2. ROR icon City University of Hong Kong
  • 3. ROR icon California Institute of Technology

Abstract

Electrochemically mediated carbon capture presents an energy-efficient and cost-effective strategy to combat climate change due to its ability to utilize renewable energy and operate at ambient conditions. However, many current approaches suffer from operational instability and limited scalability potential due to a lack of reliable, low-cost redox-active absorbent materials. Here, we introduce a class of chemically robust and economical redox-tunable Brønsted acids to electrify amine carbon capture. The redox-tunable acids exhibit a reversible tunability in pKa spanning over 20 units in organic solvents in response to electrochemical potential, thereby enabling the regeneration of classic amines for CO2 separation via proton-coupled electron transfer. Remarkably, the RAs maintain their chemical integrity for over 400 h of operation in a symmetric carbon capture flow cell under 10% CO2 and 21% O2 at ambient temperature and pressure. By harnessing electrification, our approach can effectively mitigate shortcomings inherent to thermochemical carbon capture processes, facilitating a more sustainable drop-in replacement for incumbent amine scrubbing.

Copyright and License

© The Author(s) 2025

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

Acknowledgement

The authors acknowledge financial support from the Johns Hopkins University, the David and Lucile Packard Foundation, and the Arnold and Mabel Beckman Foundation. A.L. and Y.L. acknowledge financial support from the National Science Foundation (award number 2237096). X.L. acknowledges the financial support from the City University of Hong Kong (grant number 9382002). C.B.M. and W.A.G. acknowledge support from the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award No. DE-SC0021266. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 using NERSC award BES-ERCAP0024109.

Supplemental Material

Supplementary Information

Transparent Peer Review file

Data Availability

The data generated or analyzed during this study are included in the manuscript and its Supplementary Information. The source data underlying Figs. 2–8 and Supplementary Figs. 10, 15, 16, 18, 19, 21–23, and 25–29 are provided as a Source Data file. The atomic coordinates of the optimized computational models have been deposited in the Zenodo Database [https://doi.org/10.5281/zenodo.15132348]. Source data are provided with this paper.

Source Data

Conflict of Interest

The authors declare no competing interests.

Additional details

Funding Caltech Custom Metadata
Created:
July 23, 2025
Modified:
July 23, 2025