Transport properties and electrochemical activity of YBa(Co,Fe)(4)O-7 cathodes


The layered phases derived from YBaCo4O7 exhibit a relatively low thermal expansion, significant mixed conductivity and attractive electrochemical activity in contact with doped LaGaO3 solid electrolyte. These properties may be of interest for intermediate-temperature SOFC cathodes. Moderate doping of yttrium-barium cobaltite with iron decreases slightly the total conductivity, predominantly p-type electronic, and have no essential effect on the oxygen ion transport and cathodic polarization at 1073 K. However, hexagonal YBaCo4O7, where the average cobalt oxidation state is +2.25, and its derivatives appear metastable at temperatures below 1050-1100 K. Oxygen uptake at intermediate temperatures in air leads to the phase decomposition, accompanied by increasing conductivity and dramatic volume contraction. (c) 2006 Elsevier B.V. All rights reserved.

subject category

Chemistry; Physics


Tsipis, EV; Kharton, VV; Frade, JR

our authors

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".