The Preparation And Properties Of Ce_xZr_1-xO₂ And ?YSZ?_1-x?Fe₂O₃?_x

Ce_xZr_1-xO₂ was synthesized by low-temperature solid-solid reaction method.The phase structure,micro-morphology,thermal expansion properties,thermal shock resistance,total conductivity and electronic conductivity of Ce_xZr_1-xO₂ were characterized by XRD,SEM,thermal expansion instrument,thermal shock instrument,DC Van Der Pauw method and DC polarization method?Hebb-Wagner?,respectively.The effects of CeO2 doping on properties of Ce_xZr_1-xO₂ solid solution were investigated.The XRD results indicate that the Ce0.25Zr0.75O2 powder is t-ZrO2,while the Ce0.75Zr0.25O2 powder is c-CeO2.The EDS results show that the molar ratios of Ce to Zr are consistent with the stoichiometric ratio of Ce_xZr_1-xO₂.The coefficient of linear expansion of Ce_xZr_1-xO₂ is in 13.27×10-6?-14.72×10-6·K-1 at temperature range from ambient temperature to 1400 ?.The thermal shock resistance of Ce_xZr_1-xO₂ is poor.The total conductivity and electronic conductivity of Ceo.75Zro.25O2 are maximum,reaching to 1.02x10-2 S·cm-1 and 1.02×10-4 S·cm-1,respectively,while the total conductivity and electronic conductivity of Ce0.25Zr0.75O2 are minimum,reaching to 2.72×10-4 S·cm-1 and 4.96x10-6 S·cm-1,respectively,at 850 ?.The?4.167YSZ?_1-x?Fe₂O₃?x and?9YSZ?_1-x?Fe₂O₃?solid solution materials were synthesized by chemical coprecipitation method.The phase structure,thermal shock resistance,total conductivity and electronic conductivity of?YSZ?_1-x?Fe₂O₃?x were characterized by XRD,thermal shock instrument,DC Van Der Pauw method and DC polarization method?Hebb-Wagner?,respectively.The effects of Fe₂O₃ doping on properties of?YSZ?_1-x?Fe₂O₃?x solid solution were investigated.The XRD results indicated that the solubility of Fe₂O₃ in 4.167YSZ is in 7.82?9.03mol%,while the solubility of Fe₂O₃ in 9YSZ is in 6?7.82mol%.The XRD results also show that the?4.167YSZ?_1-x?Fe₂O₃?x?x=0,0.0105,0.0433,0.0782?powders are c-ZrO2 and t-ZrO2,while?9YSZ?_1-x?Fe₂O₃?x?x=0,0.0105,0.0433,0.06?powders are c-ZrO2.The thermal shock resistance of?YSZ?_1-x?Fe₂O₃?x is excellent and the loop count is more than 30 times.In air atmosphere,the conductivity of?9YSZ?]1-x?Fe₂O₃?x are higher than that of?4.167YSZ?_1-x?Fe₂O₃?x.For example,the total conductivity and electronic conductivity of?9YSZ?0.9895?Fe₂O₃?0.0105 are maximum in?9YSZ?_1-x?Fe₂O₃?x,the values of which are 1.72×10-2 S·cm-1 and 6.30×10-3 S·cm-1 at 750 ?,respectively.The total conductivity and electronic conductivity of?4.167YSZ?0.9567?Fe₂O₃?0 0433 are maximum in?4.167YSZ?_1-x?Fe₂O₃?x,the values of which are 5.78×10-3 S·cm-1 and 4.19×10-4 S·cm-1 at 750 ?,respectively.