Enhanced Oxygen Reduction Reaction of LSCF Cathode Material Added with NiO for IT-SOFC

• Published in: Engineering Journal
• Main Author: Rosli A.Z.M.; Osman N.; Somalu M.R.; Hamid N.A.
• Format: Article
• Language: English
• Published: Chulalongkorn University, Faculty of Fine and Applied Arts 2022
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85139186745&doi=10.4186%2fej.2022.26.9.11&partnerID=40&md5=38c56ab20ad94e69a4ee1406fdfebe61

La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) is one of the mixed ionic electronic conductors that could be feasibly used in an intermediate temperature solid oxide fuel cell (IT-SOFC). In this study, LSCF and NiO were prepared using a modified Pechini method and calcined at three different temperatures ranging from 600 °C to 900 °C. The prepared LSCF was added with 5% NiO (denoted as LSCF-NiO) as cathode material. The physical and electrical properties of the prepared cathode were investigated. X-ray diffraction data revealed that at calcination temperatures of 600 °C–900 °C, NiO and LSCF maintained their phases and conformed the cubic structure for NiO and orthorhombic structure for LSCF. The calcination temperature showed significant influence on the particle size of the prepared LSCF-NiO, as depicted by scanning electron microscopy (SEM), and all the powders reached a nanoscale size. The SEM cross section of LSCF-NiO layer on gadolinium-doped cerium electrolyte showed an acceptable percentage of cathode porosity and good adhesivity at cathode/electrolyte interface. Energy dispersive X-ray analysis further verified the purity of the samples. Brunauer–Emmett–Teller surface area analysis was conducted, and the results revealed a trend of decreased surface area with an increase in calcining temperature. At an operating temperature of 800 °C, the electrochemical impedance spectroscopic results showed that LSCF-NiO 800 had a low Rp of 0.07 Ω cm2, and its Ea was found to be 159.5 kJ/mol, indicating that LSCF-NiO 800 is fit to be used as cathode material in IT-SOFC application. © 2022, Chulalongkorn University, Faculty of Fine and Applied Arts. All rights reserved.