پديدآورندگان :
Akbari Zohreh zohreh.akbari@ut.ac.ir Master of Science student of Materials Science and Engineering, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran, Iran , Babaei Alireza alireza.babaei@ut.ac.ir Assistant Professor of Materials Science and Engineering, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran, Iran , Ataie Abolghasem aataie@ut.ac.ir Professor of Metallurgy and Materials Engineering, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran, Iran
كليدواژه :
La2NiO4 , solid oxide cell , LSM , electro catalyst , infiltration
چكيده فارسي :
In this study, lanthanum nickelate (La2NiO4 (LNO)) as a mixed ionic and electronic conductor (MIEC) has been infiltrated into porous structure of strontium doped lanthanum manganite (LSM) oxygen electrode of solid oxide cells. The effects of temperature and infiltration on the impedance spectra was investigated under open circuit voltage (OCV) condition. X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM) results showed formation of pure ruddlesden popper phase of LNO and uniform distribution of LNO into the porous LSM backbone. To characterize electrochemical behavior of pure and LNO infiltrated LSM oxygen electrode, electrochemical impedance spectroscopy (EIS) measurement at temperature range of 650-850 °C at intervals of 50 °C was carried out. Results showed that infiltration of 2M LNO, reduced polarization resistance of pure LSM by 90% (from 24.61 to 2.52 Ω.cm2) and 83% (from 1.36 to 0.23 Ω.cm2) at 650 °C and 850 °C, respectively. In addition, calculated activation energy of oxygen oxidation/reduction reactions in both infiltrated (124 kJ.mol-1) and non-infiltrated electrodes (103 kJ.mol-1) also showed enhancement of activation phenomena on LSM electrode. Therefore, infiltration of LNO into LSM backbone by extending the reaction sites to the bulk of the electrode is a promising approach to achieve better electrochemical performance.
