Effect of Sr\(^{2+}\) Addition on the Structural Properties of Ce0.8Gd0.2O2-\(\delta\)(GDC) Electrolyte for Low Temperature Solid Oxide Fuel Cell Application

Abstract

Ceria-based materials have found potential application as electrolyte materials for the intermediate temperature (500-750°C) solid oxide fuel cell application (IT-SOFC). Among several trivalent rare earth substituted ceria electrolytes, Ce1-xGdxO2-\(\delta\)(CGO) and Ce1-x SmxO2-\(\delta\) (SDC) exhibit conductivity exceeding that of YSZ at 1073 K (>0.1 S cm-1). This paper reports the effect of Sr²⁺ addition on the structural, and microstructural properties of Ce0.8Gd0.2O2-\(\delta\)(GDC) electrolyte for low-temperature solid oxide fuel cell application. The Sr²⁺ (0, 0.5, 1 and 2 mol %) doped GDC solid electrolytes were prepared by solid-state method. The synthesized pellets were characterized using X-ray diffraction, Scanning Electron Microscopy and Raman Spectroscopy. The sintered densities of the samples are around 95%. XRD study reveals the cubic fluorite structure. The XRD study reveals cubic structure lattice parameters as well as crystallite size increase with increasing Sr²⁺ content. The microstructure of the samples resulted in grain sizes in the range of 4.3 to 0.868 \(\mu\)m. Raman spectra also confirm the presence of a GDC single phase.