The Electrical Properties of Zr Doped Ce0.6Y0.4O2- δ Solid Electrolytes for Solid Oxide Fuel Cell Applications

Abstract

Ionic conducting solid electrolytes based on doped ceria has been studied widely. In this work, we are studying the effect of Zr4+ substitution on the solid electrolyte system Ce0.6-xZrxY0.4O2-δ where x = 0, 0.2, 0.4, and 0.6. The samples were synthesized by mechanical milling and the evolution of their structure with milling time was analyzed by X-ray diffraction (XRD). The milled powders were uniaxially pressed and sintered at different temperatures (1200 and 1500 °C) and the morphology was analyzed by scanning electron microscopy (SEM) and the electrical properties were measured using impedance spectroscopy. XRD analysis shows the formation of fluorite type cubic phases after 20 h of milling and with increasing the sintering temperature from 900 to 1200 °C shows the transformation of cubic fluorite phase to a tetragonal phase. The analysis of electrical properties shows a decrease in conductivity with the substitution of Zr4+ in Ce0.6-xZrxY0.4O2-δ oxide.