Mitigating cathode blocking in the advanced electrochemically mediated amine regeneration CO₂ capture system by asymmetric copper foam electrode design

Electrochemically mediated amine regeneration (EMAR) technology is a promising CO₂ capture method because of the theoretically high capture efficiency and low operating temperature. However, challenges still remain in high energy consumption and poor electrode cycling stability. This work innovatively proposed an asymmetric Cu-Foam electrode based EMAR CO₂ capture system to mitigate cathode blocking effects and improve energy efficiency. Electrochemical tests demonstrate the Cu-Foam electrode can accelerate reaction kinetics, enhance diffusion and lower resistances, achieving a 42.1 % reduction in CO₂ desorption energy consumption compared to that of traditional Cu-Plate electrode. Key optimizations were implemented, including adjustments to electrode spacing, applied current, and the introduction of a novel asymmetric electrode configuration. Results show that narrower electrode spacing and higher current can efficiently enhance the cathodic performance, while the novel asymmetric electrode configuration, specifically enlarging the cathode area, effectively mitigates cathode blocking and reduces the energy consumption. Cycling stability of the proposed system was verified through polarity-switching tests, showing stable desorption performance and electrode structure after 10 cycles. At a current density of 60 A/m², the proposed system achieved a desorption energy consumption of 28.05–33.84 kJ_e/mol CO₂, which outperforms most existing electrochemical capture technologies. Results indicate that the proposed asymmetric Cu-Foam electrode configuration can effectively alleviate the cathode blocking effect and reduce the energy consumption of the EMAR CO₂ capture system, contributing to the practical application of advanced electrochemical carbon capture technologies.