Enhancement of Oxygen Surface Exchange at the Hetero-interface of (La,Sr)CoO[sub 3]/(La,Sr)[sub 2]CoO[sub 4] with PLD-Layered Films

Abstract

The preferential site for oxygen isotope exchange was investigated on layered films of La2-x Srx CoO4 (x=0.5,1.0) / La0.6 Sr0.4 CoO3 prepared by pulsed laser deposition (PLD) on a polycrystalline Ce0.9 Gd0.1 O1.95. An isotope exchange experiment was performed at 773 K in O 18 -enriched oxygen of 0.2× 105 Pa. Three-dimensional imaging of secondary ion mass spectrometry (SIMS) was carried out to visualize the isotope distribution. The SIMS images suggested that there are fast oxygen-incorporation paths along the hetero-phase interface of La2-x Srx CoO4 / La0.6 Sr0.4 CoO3. The results have reproduced our former findings on the fast oxygen surface exchange with La2-x Srx CoO4 / La0.6 Sr0.4 CoO3 composite polycrystals. © 2008 The Electrochemical Society.