Investigation of Structural, Electrical and Electrochemical Properties of La0.8Sr0.2Mn1−xScxO3−δ As Cathode on Yttria-Stabilized Zirconia Electrolyte for Intermediate Temperature Solid Oxide Fuel Cell Fabricated by One Step Dry Pressing Method

La0.8Sr0.2Mn1−xScxO3−δ perovskite oxides (x = 0.00, 0.05, 0.10, 0.15) were systematically examined as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). This study encompassed structural attributes, temperature-dependent weight variations, the electrical conductivity of La0.8Sr0.2Mn1−xScxO3−δ compositions, and the single-cell electrochemical performance of La0.8Sr0.2Mn1−xScxO3−δ on yttria-stabilized zirconia (YSZ). Further characterizations were carried out through powder X-ray diffraction (XRD), thermogravimetric analysis, DC four-probe method, and impedance spectroscopy, respectively. The X-ray diffraction (XRD) analysis revealed a clear correlation between the increase in Sc3+ content at the B-site and an increase in both the lattice parameter and lattice volume. The electrical conductivity of La0.8Sr0.2Mn1−xScxO3−δ compounds at 750 °C were found to be 137.941, 198.07, 119.789, and 61.036 S cm−1 for x = 0.00, x = 0.05, x = 0.10, and x = 0.15, respectively. When combined with YSZ in a single cell, the area-specific resistances for La0.8Sr0.2Mn1−xScxO3−δ were varied between 0.56 and 2.2 Ω cm2. La0.8Sr0.2Mn0.95Sc0.05O3−δ exhibited enhanced electrocatalytic activity, with an exchange current density of 39.35 mA cm−2 at 750 °C suggesting the composition as a potential candidate for cathode material in IT-SOFC.