Solid electrolyte for intermediate temperature solid oxide fuel cell (IT-SOFC) is a challenge for material researchers. However, Gd doped ceria (CGO) found to be a promising electrolyte among the other competitive materials. In the present investigation, we report the structural and electrical properties of CGO thin films prepared by spray pyrolysis technique. The process parameters were optimized for synthesizing Ce0.9Gd0.1O1.95 (CGO10) films. Films were characterized by XRD and EDS and are observed to be phase pure. The SEM showed the dense and uniform film growth. The dc conductivity measured is of the order of 0.5S/cm at 623K.

Intermediate temperature Solid Oxide Fuel Cell (IT-SOFC) shows number of advantages over high temperature SOFCs (HT-SOFCs), which includes smaller thermal mismatch between its components, rapid startup with less energy consumption etc. In the present paper, we are presenting the synthesis of ceria based oxygen ion conductor as an electrolyte for the low temperature SOFC. The bulk Gd0.1Ce0.9O1.95 materials have been prepared using ceramic route. Since sintering of this oxide is a crucial parameter, which affects the micro-structural and electrical properties, the green pellets were sintered at 1400, 1500 and 1600C. The synthesized samples were characterized for their structural, elemental, morphological and electrical properties using XRD, EDAX, SEM and dc conductivity, respectively. The density measurements were done for estimation of porosity before and after sintering.

In the present research work spray pyrolysis technique (SPT) is employed to synthesize GDC (10%Gd doped ceria) thin films on anode-grade-ceramic substrate (porous NiO-GDC). The film/substrate structure was characterized for their micro-structural and electrical properties along with their interfacial-quality. By optimization of preparative parameters of SPT and modification of surface of anode grade ceramic substrate, we were able to prepare the GDC films having thickness of the order of 13µm on NiO-GDC substrate. Further to improve the interfacial quality and densification of film, annealing of structure at 1000°C/8h were carried out. GDC films were fully dense (>96%), forming a gas-tight interface with substrate. Impedance measurements revealed that grain interior conductivity for GDC/NiO-GDC half-cell was of the order of 0.1S/cm at 500°C which is the desired conductivity for successful operation of SOFC. The activation energy for grain-interior and grain-boundary conduction estimated for GDC/NiO-GDC was 1.07eV and 0.93eV, respectively