CHAPTER 2: Electrolyte Materials for Solid Oxide Fuel Cells (SOFCs)

Solid oxide fuel cells (SOFCs) have aroused worldwide attention for their high conversion efficiency, zero emissions, and fuel flexibility. Generally, a SOFC consists of an anode, a cathode and a electrolyte. The electrolytes usually exert a crucial role in the performance of SOFCs. The normal electrolyte materials could be generally divided into two subclasses: oxygen ion and proton-conducting electrolyte ones, based on their different types of conduction mechanisms. In this chapter, we describe the requirements for the materials as the electrolytes of SOFCs and the recent developments of oxygen-ion conducting electrolyte, proton-conducting electrolyte and dual-phase composite electrolyte materials. Major attention is paid to the influences of structures, preparation and modified methods on the ion conduction properties of fluorite and perovskite electrolyte materials of SOFCs.