Enhanced Oxygen Reduction Reaction of LSCF Cathode Material Added with NiO for IT-SOFC
Keywords:cathode, LSCF-NiO, characterization, modified sol-gel method, IT- SOFC
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.
Authors who publish with Engineering Journal agree to transfer all copyright rights in and to the above work to the Engineering Journal (EJ)'s Editorial Board so that EJ's Editorial Board shall have the right to publish the work for nonprofit use in any media or form. In return, authors retain: (1) all proprietary rights other than copyright; (2) re-use of all or part of the above paper in their other work; (3) right to reproduce or authorize others to reproduce the above paper for authors' personal use or for company use if the source and EJ's copyright notice is indicated, and if the reproduction is not made for the purpose of sale.