Continuous carbon capture in an electrochemical solid-electrolyte reactor

Peng Zhu; Zhen-Yu Wu; Ahmad Elgazzar; Changxin Dong; Tae-Ung Wi; Feng-Yang Chen; Yang Xia; Yuge Feng; Mohsen Shakouri; Jung Yoon Timothy Kim; Zhiwei Fang; T Alan Hatton; Haotian Wang

doi:10.1038/s41586-023-06060-1

Continuous carbon capture in an electrochemical solid-electrolyte reactor

Nature. 2023 Jun;618(7967):959-966. doi: 10.1038/s41586-023-06060-1. Epub 2023 Jun 28.

Authors

Peng Zhu^#¹, Zhen-Yu Wu^#¹, Ahmad Elgazzar¹, Changxin Dong², Tae-Ung Wi¹, Feng-Yang Chen¹, Yang Xia¹, Yuge Feng¹, Mohsen Shakouri³, Jung Yoon Timothy Kim¹, Zhiwei Fang¹, T Alan Hatton⁴, Haotian Wang^{5

6

7}

Affiliations

¹ Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, USA.
² Department of Materials Science and NanoEngineering, Rice University, Houston, TX, USA.
³ Canadian Light Source Inc., University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
⁴ Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
⁵ Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, USA. htwang@rice.edu.
⁶ Department of Materials Science and NanoEngineering, Rice University, Houston, TX, USA. htwang@rice.edu.
⁷ Department of Chemistry, Rice University, Houston, TX, USA. htwang@rice.edu.

^# Contributed equally.

PMID: 37380692
DOI: 10.1038/s41586-023-06060-1

Abstract

Electrochemical carbon-capture technologies, with renewable electricity as the energy input, are promising for carbon management but still suffer from low capture rates, oxygen sensitivity or system complexity^1-6. Here we demonstrate a continuous electrochemical carbon-capture design by coupling oxygen/water (O₂/H₂O) redox couple with a modular solid-electrolyte reactor⁷. By performing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) redox electrolysis, our device can efficiently absorb dilute carbon dioxide (CO₂) molecules at the high-alkaline cathode-membrane interface to form carbonate ions, followed by a neutralization process through the proton flux from the anode to continuously output a high-purity (>99%) CO₂ stream from the middle solid-electrolyte layer. No chemical inputs were needed nor side products generated during the whole carbon absorption/release process. High carbon-capture rates (440 mA cm^-2, 0.137 mmol_CO2 min^-1 cm^-2 or 86.7 kg_CO2 day^-1 m^-2), high Faradaic efficiencies (>90% based on carbonate), high carbon-removal efficiency (>98%) in simulated flue gas and low energy consumption (starting from about 150 kJ per mol_CO2) were demonstrated in our carbon-capture solid-electrolyte reactor, suggesting promising practical applications.