Chemical Compatibility of A-site Deficient La Substituted SrTiO_3 Anode and Stabilized Zirconia Electrolyte

摘要

To investigate the chemical compatibility of A-site deficient LST anode and stabilized zirconia electrolyte, (La_(0.25)Sr_(0.75))_xTiO_3 (x=0.86, 0.88, 0.885, 0.887 and 0.89) powders were prepared by sol-gel method. TiO_2 precipitated in each LST sample except LST-0.89. The amount of TiO_2 precipitated in A-site deficient LST increased with increasing A-site deficiency concentration. Phase change of as-prepared LST and ScSZ composite pellets after annealing at 1200°C in air was characterized by XRD. Diffusion of Ti from LST into ScSZ at elevated temperature was enhanced with increasing TiO_2 precipitated in LST. Diffusion of Zr and Sc from ScSZ into LST occurred in LST-0.89/ScSZ, LST-0.887/ScSZ, LST-0.885/ScSZ and LST-0.86/ScSZ pellets. No obvious phase change was observed in LST-0.88/ScSZ; hence LST-0.88 was considered to possess relatively good chemical compatibility with ScSZ.