制备与表征
(南京理工大学 化工学院, 江苏 210094)
摘 要: 采用尿素燃烧法制备了Zr掺杂MCeO3（M=Ca、 Sr、 Ba）型钙钛矿质子固体电解质前驱体粉末, 经X射线衍射(XRD)和热重-差热(TG-DTA)分析可知, 在600 ℃下煅烧前驱体粉末得到纳米级细小钙钛矿结构晶体, 且该晶体在H2S气氛、 700 ℃下保持化学稳定。 粉末于200 MPa下等静压成型, 高温烧结6 h后, 固体电解质样品密度为理论密度的92％以上。 利用恒电位仪测定3种电解质片CaCe0.9-xZrxY0.1O3(CCZY))、 SrCe0.9-xZrxY0.1O3(SCZY)和BaCe0.9-xZrxY0.1O3（BCZY）（x=0.1~0.3）组成的水蒸气浓差电池, 电动势可验证固体电解质的质子导电性的强弱, 电池电动势的大小顺序为BCZY＞SCZY＞CCZY; 且随着温度的升高, 电动势逐渐增大, 但达到700 ℃后, EMF值逐渐趋于平缓； 在中温范围（500～750 ℃）内, BCZY的电导率最高可达到10-2S/cm以上, SCZY的也接近10-2 S/cm, 这有利于减小固体氧化物燃料电池的欧姆损失。
关键字: MCeO3固体电解质； 固体氧化物燃料电池； 水浓差电池
by Zr4+ and Y3+
（School of Chemical Engineering,
Nanjing University of Science and Technology, Nanjing 210094, China）
Abstract: The urea combustion method was adopted to prepare proton conductor MCeO3（M=Ca,Sr,Ba） precursor powders doped with Zr. From the XRD patterns and thermal analysis, 600 ℃ is the reasonable calcination temperature for MCeO3 to obtain fine powders with perovskite structure, which is stable in H2S atmosphere under 700 ℃. The solid electrolyte with 92% theory density are obtained after the powders were isostatically pressed at 200 MPa and then sintered for 6 h. The electromotive force (EMF) value of the steam concentration cell constructed by CaCe0.9-xZrxY0.1O3, SrCe0.9-xZrxY0.1O3, BaCe0.9-xZrxY0.1O3(noted as CCZY, SCZY, BCZY, respectively) as solid electrolyte were measured on potentiostat. The magnitude order of EMF value is BCZY＞SCZY＞CCZY, EMF value increases with the increase of temperature, and keeps steady at above 700 ℃. At 500-750 ℃, the biggest conductivity of BCZY reaches above 10-2 S/cm, while that of SCZY approaches 10-2 S/cm, which demonstrates that the two material are favorable for the reducing ohmic loss in the solid oxide fuel cell.
Key words: MCeO3 solid electrolyte; solid oxide fuel cell; steam concentration cell
