Design and fabrication of a novel Ni-basalt composite cathode for efficient electrochemical reduction of CO2 in solid oxide electrolysis cells

Solid Oxide Electrolysis Cell (SOEC) is an effective technology for converting carbon dioxide (CO 2 ) into valuable products, like carbon monoxide (CO) and oxygen (O 2 ) using renewable electricity. An ideal electrode material for SOECs should possess fast electrode kinetics, high energy efficiency, and low cost. However, poor CO 2 adsorption at the cathode limits practical application, making design of highly active and durable cathodes a significant challenge. This study introduces a novel Ni-basalt cathode for CO 2 -SOECs. The Ni-basalt composite cathode, is prepared by pressing method and reduction treatment, demonstrates a high concentration of oxygen vacancies, which creates more active sites that enhance CO 2 adsorption and reduction performance. The resulting SOEC demonstrates a high current density (480 mA/cm 2 ), a low polarization resistance (1.91 Ω cm 2 ) at 1.6 V and at 800 °C, and high CO production (7.45 ml min −1 cm −2 ) with a faradaic efficiency greater than 90 %, indicating its potential for advancing CO 2 conversion.