Novel Composite Electrolytes for Solid Oxide Fuel Cell Applications

Abstract

Gadolinia doped ceria is a good candidate for use as an alternative to zirconia for solid oxide fuel cell electrolytes. This is due to its higher ionic conductivity at reduced temperatures. However, doped ceria has a number of disadvantages such as reduced strength and electronic conductivity. An investigation has been carried out to characterise novel composite structures consisting of tetragonal zirconia particles in a doped ceria matrix. Results indicate that an increase in strength can be produced in the ceria by addition of zirconia particles, however, this is dependent on particle size and heat treatment. A structural analysis of the composite structures was carried out using scanning electron microscopy. Electrical properties were determined using a Solartron dielectric test system.