Advance in the Electrolyte Material System and Optimization Strategies of Solid Oxide Electrolysis Cells

Solid oxide electrolysis cells (SOECs) are a new type of highly efficient water electrolysis technology for hydrogen production, showing great potential for converting and storing renewable energy and mitigating the greenhouse effect. Electrolytes are key components of SOECs, but single and unmodified electrolytes currently have certain limitations in terms of efficiency and stability. This paper reviews the basic principles of SOECs, the types of electrolytes corresponding to the two ion conduction modes, and related doping modification optimization strategies. By introducing heteroatomic ions such as Gd3+and Y3+through doping modification to regulate oxygen vacancy concentration and optimize ion migration channels, the performance of the electrolyte can be comprehensively enhanced. A comprehensive summary of the various types of electrolytes and doping modification schemes for SOECs can help new researchers get started. Proton-conducting (H-SOEC) is a key area of future research, as it offers significant conductivity at lower operating temperatures, which is crucial for extending device life and reducing manufacturing costs. This will enable the large-scale commercialization of SOECs.