Research Progress on Electrolytes for Intermediate and Low Temperature Solid Oxide Fuel Cells

Reducing the temperature for operating the solid oxide fuel cells (SOFCs) is crucial for advancing their commercialization and large-scale application. With the characteristics of clean and environmentally friendly as well as high energy conversion efficiency, it has been considered as a promising choice for future large-scale power generation devices. However, the drawback of high temperature working condition obstructed its wide utilization. As one of the core components of SOFCs, searching for electrolyte materials which are able to be utilized and modified under relative intermediate and low temperatures is an important method to improving the performance under such temperature conditions. CeO2-based materials, proton-conducting electrolytes, and semiconductor oxide materials have been widely studied for their high ionic conductivity, low electronic conductivity, and excellent performance after modification. This paper focus on the characteristics and principles of these three types of electrolyte materials, illustrating the advantages and drawbacks of different materials and gives strategies for optimizing material performance in practical applications as well as suggestions for the future development of intermediate and low-temperature electrolytes to further promote the utilization of SOFCs.