Role of Ba2+ substitution on structural, thermal, dielectric and electrical properties of La1-xBaxMn0.50Fe0.50 O3 {0.10 ≤ x ≤ 0.40} cathode for SOFCs

Abstract

La1-xBaxMn0.50Fe0.50 O3 {x = 0.10,0.20,0.30 and 0.40} perovskite fabricated by use of solid-state method and the prepared ceramic has been characterized to find the influence of Ba2+ on its thermal, structural, dielectric and electrical behavior. Result of X-ray diffraction noticeably shows single phase crystalline behavior and hexagonal crystal structure. Density calculation confirmed that Ba2+ addition decreased its value. TGA confirm weight gain above 300 °C temperature in the material. Thermal expansion coefficient have been measured for x = 0.10 and 0.40 sample and its value is 10.3 × 10−6 °C−1 and 9.2 × 10−6 °C−1 respectively up to 800 °C temperature. Electric and dielectric behavior confirmed non-Debye relaxation behavior of the material. The highest conductivity is found to be 126.44 Scm−1 and 143.38 Scm−1 for x = 0.10 at 600 °C and 291.86 Scm−1 and 349.25 Scm−1 at 800 °C temperature for x = 0.40 which confirm that with Ba2+ doping conductivity increases. Activation energy falls with Ba2+ content. Results verified that the present fabricated perovskites are suitable to be used as cathode for intermediate temperature SOFCs.