Zinc Oxide On Yttium-doped Cerium Oxide Of Aintering And Ionic Conductivity

• Main Authors: Shie, Chnigyi, 謝青嶧
• Other Authors: Lin, Jyungdong
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/15229832973184942120

碩士 === 義守大學 === 材料科學與工程學系 === 100 === This study attempts to transition metal oxides (Zn, Cu, Co) as sintering additives, doped to the Ce0.85Y0.15O2-δ (CYO), due to the electrolyte of solid oxide fuel cells require high density, it is expectedadded to the transition metal oxides can increase the sintering. First, we use the Pechini method, the ammonia co-precipitation method with ammonium bicarbonate coprecipitation method to prepare the CYO powder. The results show that using the Pechini method with ammonia precipitation method CYO bulk, 94% in 1350 sintered relative density of 6 hours. Ammonia co-precipitation process is more complicated, and therefore we have chosen the Pechini method to prepare the CYO powder. Pechini method the direct preparation of Zn-CYO, doped with transition metal oxides (ZnO) to the CYO powder and urea hydrolysis, sol-gel method and the nitrate method, changes with different doping levels, sintering temperature and sintering time to explore the relative density and conductivity of. Identification by XRD analysis to determine the preparation of Zn-CYO powders, in different ways by the after sintering to determine the CYO of the cubic fluorite phase, and no impurity phase generation, and the measurement from the Archimedes method that doping Zn to the CYO electrolyte relative density than that of pure CYO also much higher. TEM, EDX evidence can see that doping Zn into the CYO powder. The optimum sintering conditions of 1250 ° C, 6 hours, the Pechini method and nitrate in the process of the law to doping of Zn, the relative density can reach 98%.Then investigate the thermal expansion coefficient, can be found from the pure CYO (P) TEC value of 17.80 × 10-6 / ℃. Doped into the Zn CYO its TEC value increased to more than 20 × 10-6 / ° C, found by the AC impedance, and its conductivity is not because the doping of Zn to the CYO powder, causing the CYO of the ionic conductivity decreased.Above results that the doping of Zn can be used as a CYO electrolyte sintering aids, and can see that doping Zn can make the sintering temperature decreased, and the Pechini method and Nitrate-doped Zn is feasible, and not of ZnO precipitated phase.