Innovative electrode designs for low-temperature electrochemical CO2 reduction with ampere-level performance

Abstract

The electrochemical carbon dioxide reduction reaction (eCO2RR) is a key technology for converting intermittent renewable energy into value-added fuels and chemicals, offering a promising pathway to re-balance the carbon cycle. However, its selectivity, stability, and energy efficiency remain insufficient to meet industrial requirements, particularly at high current densities. To advance this technology toward large-scale implementation at the industrial level, research has shifted from focusing solely on electrocatalyst optimization to a more holistic approach that integrates electrode design with reactor and system engineering. As a critical component of CO2 electrolysis systems, the electrode plays a pivotal role in mass transfer kinetics and interfacial reactions. This review provides an in-depth analysis of advanced electrode design strategies and fabrication technologies while assessing their commercialization prospects. We first outline the fundamental working principles and reaction mechanisms of cathode electrodes, establishing a foundation for next-generation electrode development. We then present a comprehensive review of recent progress in electrode structure design, covering conventional non-gas diffusion electrodes (GDEs), planar GDEs, and microtubular GDEs, with a focus on their efficiency in converting CO2 into value-added products. Additionally, we explore CO2 mass transfer mechanisms and enhancement strategies across different electrode configurations to mitigate mass transfer limitations and optimize performance. Finally, we discuss the remaining challenges and future opportunities in this field, offering insights into the design of electrodes for ampere-level and industrial-scale applications. This review aims to accelerate the commercial deployment of eCO2RR technology by providing valuable guidance for the development of high-performance electrodes.