Developing solid oxide electrolysis cells for CO₂ conversion: A critical power-to-X approach

Abstract

The substitution of traditional fossil fuels with renewable energy sources is a crucial endeavor for achieving carbon neutrality targets. However, the intermittency of solar, wind, and other renewables poses significant challenges to the power grid. Power-to-X (P2X) technologies play an essential role in enabling the efficient consumption of renewable energy. High-temperature solid oxide electrolysis cells (SOECs) to convert CO₂ offer a promising method for CO₂ conversion, allowing renewable electricity to be stored in chemical form and facilitating the resourceful utilization of carbon resources. In this paper, the mechanism of CO₂ reduction through SOECs is reviewed, two pathways for converting CO₂ to chemicals via SOECs are summarized, and the current markets and manufacturers of SOECs are elucidated. Based on this discussion and analysis, the main challenges and development directions for the large-scale application of SOECs in CO₂ conversion are further proposed.

Graphical abstract

Keywords

solid oxide electrolysis cells (SOECs) / CO₂ conversion / power-to-X (P2X)

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