中温固体氧化物燃料电池双层电解质及其制备技术的研究进展

Research Progress of Double-layer Electrolyte and Its Preparation Technology for Intermediate Temperature Solid Oxide Fuel Cells

固体氧化物燃料电池(solid oxide fuel cell,SOFC)是一种新型能源转换装置,其中电解质是其核心部件之一。为实现SOFC商业化的发展,关键因素是将SOFC从高温做向中温,而中温下固体电解质又表现出很多缺点,如CeO2基电解质低氧分压下内部产生电子电导降低了电池输出性能、ZrO2基电解质中温下电阻急剧变大、LaGaO3基电解质与电极之间的界面反应、Bi_(2)O_(3)基电解质还原气氛下还原成金属铋,这些缺点会限制材料的应用。为解决这些存在的问题,在此基础上构造双层电解质,双层电解质能够阻隔CeO2基电解质电子传导,阻隔Bi_(2)O_(3)基还原气氛下电解质还原成金属以及LaGaO3基电解质与电极间的界面扩散反应等问题,进而提升电池的输出性能。通过薄膜制备技术将ZrO2基电解质做成薄膜也可以实现中温的应用。本文对广泛研究的DOC/掺杂Bi_(2)O_(3)、掺杂ZrO2/DOC、掺杂ZrO2/稳定Bi_(2)O_(3)等体系的中温固体氧化物燃料电池双层电解质发展进行了概述,介绍了电解质薄膜的制备技术(包括脉冲激光沉积、磁控溅射、流延法以及一些化学沉积法),运用薄膜制备技术制出的双层电解质在固体燃料电池中得到广泛应用。最后对电解质薄膜化以及制备双层电解质在SOFC中的发展趋势进行了展望。

Solid oxide fuel cell (SOFC) is a new type of energy conversion device in which electrolyte is one of its corecomponents. In order to realize the development of SOFC battery commercialization, the key factor is to make SOFC from highto intlermediate temperature, and the solid electrolyte at intermediate temperature shows many shortcomings, such as the internalgeneration of electronic conductance under low oxygen partial pressure of CeO_(2)-based electrolyte, which reduces the outputperformance of the battery, the resistance of the ZrO_(2)-based electrolyte increases sharply at intermediate temperature, the interfacereaction between the LaGaO_(3)-based electrolyte and the electrode, and the reduction of the Bi_(2)O_(3)-based electrolyte tometallic bismuth in a reducing atmosphere will limit the application of the material. In order to solve these existing problems,a double-layer electrolyte is constructed on this basis. The double-layer electrolyte can block the electron conduction of theCeO_(2)-based electrolyte, block the reduction of the electrolyte to metal under the Bi_(2)O_(3)-based reducing atmosphere, and the interfacialdiffusion reaction between the LaGaO_(3)-based electrolyte and the electrode, etc. problem, thereby improving the outputperformance of the battery. The application of intermediate temperature can also be realized by making ZrO_(2)-based electrolyteinto thin film by thin film fabrication technology. In this paper, the development of double-layer electrolytes for intermediate-temperature solid oxide fuel cells in the widely studied DOC/ doped Bi_(2)O_(3), doped ZrO_(2) / DOC, and ZrO_(2) / stabilized Bi_(2)O_(3)systems is summarized, and the preparation techniques of electrolyte films (including pulsed laser deposition, magnetron sputtering,casting and some chemical deposition methods), bilayer electrolytes made by thin film fabrication technology are widelyused in solid fuel cells. Finally, the development trend of electrolyte thinning and preparation of bilayer electrolytes inSOFC is prospected.