適用於物理化學實驗及儀器分析教學之陶瓷新製程－結合溶膠－凝膠法及燃燒法製備釔鋇銅氧高溫超導體

黃其清 ； 胡文華 ； 黃廷翰

《化工》 50卷4期 (2003/08) Pp. 53-63

https://doi.org/10.29803/CE.200308.0010

摘要

本研究乃是將溶膠－凝膠法與燃燒法相結合－由乾凝膠經燃燒反應所得到之微細粉末製備釔鋇銅氧高溫超導體（YBa2Cu3O7-x，x≧0.25），並設計一適用於物理化學實驗及儀器分析教學之教材。所用原料為釔、鋇、銅之硝酸鹽，依化學計量比秤取後加水溶解，再加入與金屬硝酸鹽等莫耳數的檸檬酸，並滴加飽和氨水調整溶液pH值為７。溶液經攪拌加熱蒸發水分後，製得深褐色的乾凝膠。此乾凝膠具有可燃性，在空氣中引燃後即可得膨鬆的棕色產物，經研磨後於高溫爐中以９００、９３０°C分別鍛燒及燒結各１２小時。如此即可製得在液氮溫度下具有超導性且為單一相之釔鋇銅氧高溫超導體。在實驗過程中使用熱分析儀（TGA-DTA）及紅外線光譜（IR）分析燃燒反應過程之現象，利用Ｘ光繞射儀（XRD）分析產物相成分，以及使用掃描式電子顯微鏡（SEM）觀察產物型態，並將燒結後之釔鋇銅氧高溫超導體置於液態氮測試其磁浮特性。本教材完成後，已於中正理工學院應用化學系三年級學生之實驗課程中試教，成效良好。

關鍵字

溶膠－凝膠 ； 燃燒合成 ； 釔鋇銅氧超導體 ； 物理化學實驗 ； 儀器分析

並列摘要

In this study, an experiment entitled “Using a Novel Combining Sol-Gel and Combustion Synthesis Techniques for Preparation of Y-Ba-Cu-O Superconductor” was designed for the experimental courses of physical chemistry and instrumental analysis while the process of ceramic preparation was introduced to the students at the mean time. Y(NO3)3‧6H2O, Ba(NO3)2, Cu(NO3)2‧3H2O, citric acid and ammonia were used as starting materials to form a precursor xerogel. And then, the dried gel underwent a self-propagating combustion process when being ignited in air and yield voluminous ashes. These ashes required a relatively low temperature of calcinations (900°C/12h) to obtain the powder of YBa2Cu3O7-x superconductor with orthorhombic phase. The redox behavior and crystallization process of the dried gel were examined by thermal analyses (TGA-DTA) and infrared (IR) spectra. The samples at different stages of the experimental process were characterized in terms of X-ray diffraction (XRD) and scanning electron microscope (SEM). The sintered body demonstratedits diamangnetism at liquid nitrogen temperature.

並列關鍵字

sol-gel ； combustion synthesis ； Y-Ba-Cu-O superconductor ； experiment of physical chemistry ； instrrument analysis