Chemical Interaction between Ba2YCu3O7-δ and Substrate Materials in the Solid State

Abstract
The solid phase chemical reaction between Ba2YCu3O7-δ (BYCO) and substrate materials has been investigated quantitatively by X-ray diffraction and ac-susceptibility measurements. The twelve substrate materials examined can be classified into four groups in the order of chemical reactivity with BYCO:SrTiO3, MgO2, TiO2, Al2O322O3, CaF2. X-ray analysis indicates that Ba in BYCO is primarily responsible for the reactions with substrate materials. The electronegativity of a component in the substrate has a qualitative correlation with the reactivity of BYCO toward the substrate materials.