Effect of La[sub 2]Zr[sub 2]O[sub 7] on Interfacial Resistance in Solid Oxide Fuel Cells

Abstract

The impact of La 2 Zr 2 O 7 (LZO) on interfacial resistance (R p ) at the La 0.78 Sr 0.20 MnO 3-δ /yttria-stabilized zirconia interface was studied upon isothermal sintering at 1200°C for 2-25 h. Quantification of triple phase boundary length was performed by applying focused ion beam/scanning electron microscopy (FIB/SEM) serial-sectioning techniques and classical stereology. Electrochemical impedance spectroscopy was used to characterize the R p . The effect of LZO formation on microstructural models for R p was analyzed with respect to previous works that did not include this effect. LZO formation modifies the TPB length, rapidly increases R p , and needs to be controlled in analytical microstructural R p models. © 2010 The Electrochemical Society.