Effect of synthesis on structural, vibrational, and electrical properties of Ba_1−xCa_xCe_0.8Nd_0.2O_3−δ (BCCN, 0 ≤ x ≤ 0.01) synthesized by sol–gel auto combustion method

The present study explores a nano-grained perovskite material for use in an intermediate-temperature solid oxide fuel cell. Electrolytes with the formula Ba_1−xCa_xCe_0.8Nd_0.2O_3−δ (BCCN), where x = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05, were synthesized through the sol–gel auto-combustion process. Structural, surface morphology and vibrational analyses were conducted through XRD, SEM, FTIR, and Raman studies. Scherer’s formula revealed predicted crystallite sizes for the electrolyte materials ranging from 25.13 to 38.69 nm. Morphological assessments determined grain diameters between 1 to 3 µm. Raman spectroscopy identified the 355 cm⁻¹ vibrational mode associated with CeO6 octahedra, while FT-IR identified bands corresponding to M–O vibrations. Electrical impedance spectroscopy results indicated ionic behavior conducive to electrolytes, with overall conductivities increasing with measurement temperature. Notably, bulk conductivity surpassed grain boundary conductivity, with the highest overall conductivity observed in x = 0.05 compositions among the examined perovskite oxides.