Characterization of BaFe_0.8Zn_0.1Nb_0.1O_3-δ and BaFe_0.6Zn_0.3Nb_0.1O_3-δ Perovskite Cathode Materials for Intermediate-Temperature Solid Oxide Fuel Cells

Abstract

This study explores the potentiality of the zinc and iron-based perovskite cathode materials in intermediate temperature solid oxide fuel cells (SOFCs), for which BaFe0.8Zn0.1Nb0.1O3‑δ (BFZNO:1) and BaFe0.6Zn0.3Nb0.1O3‑δ (BFZNO:2) materials with cubic crystal phase purity were considered. These materials have been effectively synthesized by employing the sol–gel autocombustion process. The structural details and phase purity of the synthesized nanomaterials were confirmed from the data obtained from the XRD patterns, while SEM images revealed that both materials are highly porous with grain sizes of 200–250 nm and 55–65 nm for BFZNO:1 and BFZNO:2, respectively. The DC electrical conductivity of BFZNO:1 was estimated as 3.98 S/cm and that of BFZNO:2 as 3.56 S/cm at 700 °C. The BFZNO:1 exhibited a superior current density of 1360 mAcm–2, a power density of 530 mW cm–2, and an open circuit voltage of 1.29 at an intermediate temperature of 700 °C, confirming the potential of Zn and Fe-based perovskite cathode materials for application in intermediate temperature SOFCs.