Preparation And Properties Of Cathode Materials Ln_1-x Sr_xCoO_3-δ (Ln=La, Pr, Nd, Sm, Eu) Thin Film

The superfine powder of Ln_0.5Sr_0.5CoO_3-δ( Ln =La, Pr, Nd, Sm, Eu) which is used in the cathode material of solid oxide fuel cell (SOFC) were obtained by solid state reactions. We have studied the crystal structures and electrical transport properties when doping different rare-earth elements as well as the forming process of the Perovskite structure. Then the DC conductivity of the samples at different temperature has been tested.Then we have obtained La_0.5Sr_0.5CoO_3-δ thin films which are on the oxidizing yttrium steady oxidizing the zirconium (YSZ) and aluminate lanthanum (LaAlO₃) by ion-beam sputtering method. Studied and analyzed the surface composition micro-structures and chemical states.The results show that when the temperature reach 1200℃, the samples would become a steady and unitary Perovskite phase by solid state reactions. The conductive behavior at low temperature is consistent with small polaron mechanism. However the maximum of conductivity appears at about 700 ℃, and the conductivity of La_0.5Sr_0.5CoO_3-δis the biggest in the intermediate-temperature (600～850℃), so the electricity properties is best.The results of the XRD spectras show that the La_0.5Sr_0.5CoO_3-δ thin films which...