Solid Oxide Electrolysis Cells (SOECs) are among the promising pathways for electrochemically converting CO2 to CO and O2, with high energy conversion efficiency and fast electrode kinetics, thereby contributing to climate change mitigation and net-zero carbon emissions. An ideal electrode material for SOECs should possess fast electrode kinetics, high energy efficiency, and low cost. However, poor CO2 adsorption at the cathode limits practical application, making the design of highly active and durable cathodes a significant challenge.
Currently, Ni-based cathodes, mainly Ni-YSZ, Ni-GDC, and Ni-SDC, are widely employed in SOECs for CO2-RR due to their excellent electrical conductivity and catalytic activity. However, certain issues limit their large-scale application. These cathodes experience significant loss of electrical conductivity and deactivation due to the easy Ni re-oxidation, carbon deposition, and nickel agglomeration during operation.
We propose basalt as a low-cost and naturally abundant functional component for the design of advanced transition-metal-based cathodes for high-temperature CO2 electrolysis. A series of basalt-based cathodes incorporating Ni, Co, and TiO2 were designed and investigated. Characterizations revealed that the incorporation of these elements promotes oxygen-vacancy formation, enhances oxygen mobility, and generates favorable active sites for CO2 adsorption and activation. The resulting modification of the cathode surface and microstructure significantly improved the electrochemical kinetics of CO2 reduction.
The catalytic activity was evaluated using cathode-supported SOEC single cells. Ni-basalt cathode achieved a current density of 480 mA cm-2 at 800 °C and 1.6 V, while Ni-Co-basalt cathode reached 510 mA cm-2 under the same conditions. Furthermore, optimization of TiO2 incorporation resulted in a Ni-TiO2-basalt cathode reaching 373 mA cm-2 at 800 °C and 1.6 V, representing a substantial enhancement compared with the undoped cathode. The improved performance is attributed to the synergistic effects of Ni, Co, and TiO2 with basalt structure, enhancing CO2 adsorption/activation, oxygen vacancy concentration, and oxygen-ion transport.
Overall, our work demonstrates the potential of basalt-based transition-metal cathodes as efficient, durable, and cost-effective materials for CO2 electrolysis, providing a promising strategy for the development of next-generation SOECs for renewable-energy-driven CO2 conversion.

Dr. Ismail Rimeh is a researcher, holds a PhD in Chemistry from the University of Tunis El Manar (Tunisia) and the University of Montpellier (France).  From 2021 to 2022, she worked as a Research Assistant/Postdoctoral fellow at the Institute of Macromolecular Chemistry, Czech Academy of Sciences, Prague, Czech Republic. In 2022–2024, she joined the University of Chemistry and Technology, Prague, Czech Republic, as a Postdoctoral fellow. Currently, she is a research fellow at Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, in Ürümqi, China. Dr Rimeh is a recipient of the prestigious China National Overseas High-Level Youth Talent Introduction Program (QR). She got the funding from the Ministry of Science and Technology of China (MOST)-Foreign Young Experts Program as well as the "Tianchi Talent Introduction Program (Young Doctoral Project)" of Xinjiang Uygur Autonomous Region. Dr. Rimeh has published more than 20 SCI papers in high-impact international journals and has been recognized with awards at international conferences. She has actively contributed to national and international research projects, specializing in advanced material design and synthesis for applications in energy and environmental science. Her key research areas include Direct Air Capture (DAC) and electrochemical CO₂ reduction, addressing critical challenges in sustainable energy and climate change mitigation.