TITLE:
Effect of Y on the Properties of Sm-Doped Ceria for IT-SOFC Applications
AUTHORS:
V. Venkatesh, C. Vishnuvardhan Reddy
KEYWORDS:
X-Ray; Scanning Electron Microscopy; Thermal Expansion; Electrical Conductivity
JOURNAL NAME:
Journal of Modern Physics,
Vol.4 No.11,
November
22,
2013
ABSTRACT:
The co-doped ceria-based materials
with general composition formula Ce0.8-xYxSm0.2O2-δ (x = 0, 0.02, 0.04, 0.06)
were prepared through the sol-gel method. The single phase of the prepared
materials was confirmed by X-ray diffraction (XRD). The lattice parameters were
determined by least square fitting of UNIT CELL programme. The linear variation
of lattice parameter with concentration of Y
into the samarium doped ceria (SDC) indicates the validity of Vegard’s law.
The crystallite size of the samples obtained by using of Scherrer formula is in
the range from 34 nm to 49 nm. The thermal expansion studies were carried out by using
dilatometric technique in the temperature range from room temperature to 1000°C.
It was observed that the thermal expansion increased linearly with increasing
temperature for all the samples. The electrical conductivity was studied using
impedance spectroscopy. It was observed that the composition Ce0.74Y0.06Sm0.2O2-δ showed higher electrical conductivity and lower activation energy
(≈1.05 eV) than other compositions in the present investigation. This
composition is thus a possible candidate for use the electrolyte in intermediate
temperature solid oxide fuel cells (IT-SOFC).