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Rare-earth-doped BaCeO₃ and BaZrO₃ electrolytes with perovskite structure have been studied extensively in developing intermediate temperature SOFC. Traditional solid state sintering has been used to prepare the perovskite type proton conductors Ba(Ce,Zr)_1−xSc_xO_3−δ (x=0.1, 0.2). Rietveld refinement of the XRD data shows the materials as cubic in the space group Pm-3m. The unit cell parameter a decreases with Sc concentration. Thermogravimetric analysis (TGA) traces obtained for dehydrated samples on heating in a 3% H₂O/5% H₂/Ar atmosphere show that, on heating, initially the sample weight remains constant up to 400 °C and then decreases. TGA in pure CO₂ shows that Sc doping increases the chemical stability. AC impedance measurements under wet 5% H₂/Ar show that these materials are good conductors and stable under H₂ atmosphere. It also shows that bulk and grain boundary …