Engineering, Catalysis and Reaction Engineering, Materials Science and Engineering
The creation of A-site cation defects within a perovskite oxide can substantially alter the structure and properties of its stoichiometric analogue. In this work, we demonstrate that by vacating 2 and 5% of A-site cations from SrNb0.1Co0.9O3−δ (SNC1.00) perovskites (Sr1−sNb0.1Co0.9O3−δ, s = 0.02 and 0.05; denoted as SNC0.98 and SNC0.95, respectively), a Jahn–Teller (JT) distortion with varying extents takes place, leading to the formation of a modified crystal lattice within a the perovskite framework. Electrical conductivity, electrochemical performance, chemical compatibility and microstructure of Sr1−sNb0.1Co0.9O3−δ as cathodes for solid oxide fuel cells were evaluated. Among SNC1.00, SNC0.98 and SNC0.95, SNC0.95 (P4/mmm symmetry (#123)) which exhibits a large JT distortion in conjunction with charge-ordering of cobalt (Co) shows the best oxygen reduction reaction (ORR) activity at low temperature while SNC0.98 (P4mm symmetry (#99)), which displays a local JT distortion, shows the poorest performance.
Published in RSC Advances, Volume 4, Issue 77, 2014, pages 40865-40872.
© RSC Advances, 2014, Royal Society of Chemisty
Zhu, Y., Lin, Y., Shen, X., Sunarso, J., Zhou, W., Jiang, S., Su, D., Chen, F., Shao, Z. (2014). Influence of Crystal Structure on the Electrochemical Performance of A-Site-Deficient Sr 1-xNb 0.1 Co 0.9 O 3-δ Perovskite Cathodes. RSC Advances, 4(77), 40865-40872.