固態氧化物燃料電池氧化鈰鋯固溶體之合成與特性探討

Abstract

本論文利用溶膠凝膠法(sol-gel method) 合成氧化鈰鋯固溶體(Ce1-xZrxO2) 。而經由合成不同比例之鋯離子掺雜入氧化鈰結構可影響晶格的變化。在X光粉末繞射圖發現氧化鈰掺雜鋯離子並燒結至600°C後仍維持螢石結構。接著使用掃描式電子顯微鏡及穿透式電子顯微鏡觀察其形貌，並透過EDX確定理論掺雜量與實驗掺雜量相符。之後，以X射線光電子能譜儀(XPS) 分析各離子的鍵結環境及氧化態，其測試結果顯示氧化鈰鋯固溶體儲氧能力優於其它陽極材料。最後利用交流阻抗頻譜儀測試離子導電度，在鋯離子與鈰離子莫耳數比為3:7時會有最佳的離子導電度；並且將此材料與文獻上其它陽極材料相比，氧化鈰鋯固溶體擁有較佳的離子導電度。未來可做更多的電性測試確定此材料可能作為電解質使用。

In this Thesis, a series of Ce1-xZrxO2 solid solution phases were synthesized by sol-gel method. Measurements of powder X-ray diffraction (PXRD) indicate that the as prepared Ce1-xZrxO2 maintain fluorite structure. The morphological analyses are investigated by Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Elemental analyses show that the amount of Zr4+ doping into ceria is in consistent with expected data. Futher, the oxygen storage capacity could be reflected on x-ray photoelectron spectroscopy data. Moreover, the ionic conductivity is measured by impedance. The ionic conductivity curves reveal that increasing the doping amount of Zr4+ into ceria would enhance the oxygen storage capacity thus raise the ionic conductivity. In the future, this material of SOFC can be evaluated by cell testing to confirm be the better electrolyte than commercial material.