Synthesis and characterization of B-site doped La0.20Sr0.25Ca0.45TiO3 as SOFC anode materials

Abstract

In this paper, B-site doping of an optimized A-site deficient composition, calcium-doped lanthanum strontium titanate, La0.2Sr0.25Ca0.45TiO3 (LSCTA−) with Ni and Fe is presented. The doped compositions were successfully synthesized by the Pechini method and then characterized by XRD, SEM, dilatometry, ac impedance, and dc conductivity. The doped analogues preserved the orthorhombic symmetry of the parent, LSCTA−. The observed dilatometric results were correlated with the particle size. Ac impedance studies revealed their semi-conducting behaviour in air. Furthermore, the doped compositions showed higher conductivity values in reducing atmosphere. Compared to bare pre reduced LSCTA− having conductivity of 38 S cm−1, the pre reduced 5% Ni doped LSCTA− (LSCTN5) and 5% Fe doped LSCTA− (LSCTF5) showed conductivity values of 47 S cm−1 and 66 S cm−1 at 880 °C, respectively. B-site doping could affect the electrical and catalytic properties of LSCTA− materials making them viable alternatives for fuel cell applications.