Preparation And Characterization Of Solid Electrolyte And Other Materials Used In Intermediate Temperature Solid Oxide Fuel Cell

La1-xSrxGa1-yMgyO3-(x+y)/2(LSGM)material has high ionic conductivity over the large range of oxygen partial pressure at the low and intermediate temperatures, which is excellent electrolyte candidate for intermediate temperature solid oxide fuel cell. In this work, we used the solid reaction method to prepare 9 kinds of LSGM with Sr, Mg double-doped;the Ni-GDC anode with NiO 20%, 30%,40%,50% and 60%;and the La1-xSrxCoO3 cathode. The solid reaction synthetic processes,sintering properties and phase composition of the LSGM samples were investigated by TG-DTA, SEM, XRD and the Archimedes method. The electrical properties of LSGM were evaluated by DC four-terminal method and AC impedance spectroscopy.According to the LSGM preparation experimental results, the following conclusions are obtained. High quality LSGM electrolyte with perovskite phase can be obtained by using the proper solid reaction method sintered at 1500℃. It was found that the grains of LSGM were grown up according to a hexagon step mode. The conductivity of LSGM increased with the temperature increasing. As the temperature is above 600℃, the conductivity increased acutely. The conducti- vity increased with increasing of Sr doping content, however,decreased with incr- easing of Mg doping content.he conductivity of La0.83Sr0.17Ga0.9Mg0.1O2.865 sintering for 6h is highest, the 0.1185S/cm conductivity at 900℃was similar to that of samples measured by other researchers.According to the Ni-GDC anode preparation experimental results, the follo- wing conclusions are obtained. The XRD patterns of cube fluorite Ce0.8Gd0.2O1.9 and face cube NiO were appeared after sintering for 5h at 1250℃, respectively. The conductivities of Ni-GDC after reduction were higher as 104~105 magnitude level than those before reduction.According to the LSCO cathode preparation experimental results, the following conclusions are obtained. The perovskite phase structure was formed after LSCO sintered at 1250℃for 5h. In the whole testing temperature range, the conductivity of La1-xSrxCoO3 was up to 850~1510S/cm.With the temperature increasing, the total conductivity increased to the maximum value firstly, and then reduced. The ionic conductivity increased with the temperature increasing. The conductivity increased with the increasing of Sr doping content. But the compatibilities between cathode and electrolyte were not very well. So we should consider to prepare the complex cathode.LSGM material is a kind of excellent electrolyte in SOFC. However, finding compatible electrode is very important in the future.