制備與表征
(南京理工大學 化工學院, 江蘇 210094)
摘 要: 采用尿素燃燒法制備了Zr摻雜MCeO3（M=Ca、 Sr、 Ba）型鈣鈦礦質子固體電解質前驅體粉末, 經(jīng)X射線衍射(XRD)和熱重-差熱(TG-DTA)分析可知, 在600 ℃下煅燒前驅體粉末得到納米級細小鈣鈦礦結構晶體, 且該晶體在H2S氣氛、 700 ℃下保持化學穩(wěn)定。 粉末于200 MPa下等靜壓成型, 高溫燒結6 h后, 固體電解質樣品密度為理論密度的92％以上。 利用恒電位儀測定3種電解質片CaCe0.9-xZrxY0.1O3(CCZY))、 SrCe0.9-xZrxY0.1O3(SCZY)和BaCe0.9-xZrxY0.1O3（BCZY）（x=0.1~0.3）組成的水蒸氣濃差電池, 電動勢可驗證固體電解質的質子導電性的強弱, 電池電動勢的大小順序為BCZY＞SCZY＞CCZY; 且隨著溫度的升高, 電動勢逐漸增大, 但達到700 ℃后, EMF值逐漸趨于平緩； 在中溫范圍（500～750 ℃）內(nèi), BCZY的電導率最高可達到10-2S/cm以上, SCZY的也接近10-2 S/cm, 這有利于減小固體氧化物燃料電池的歐姆損失。
關鍵字: MCeO3固體電解質； 固體氧化物燃料電池； 水濃差電池
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
