鈦酸鍶(Strontium titanate, SrTiO3)為一鈣鈦礦型結構之功能性陶瓷材料，其同時具有高化學穩定性和高熱穩定性，故廣泛應用於機械、電子及陶瓷等領域。亦因其具備介電損失低、介電常數高、電子與離子之混和傳導體等特性，故適用於之固態氧化物燃料電池之陽極材料。
本研究之目的即增加多晶SrTiO3的(111)平面以提升Σ3共位晶界之比例，實驗方法是藉由添加含有羥基(⸻ OH)的不同醇類添加物製備SrTiO3粉體，於起始粉體之表面形成較多的(111)平面。實驗中使用硝酸鍶與異丙醇氧鈦作為前驅物，並分別添加硝酸及硝酸與丙三醇、1,2-丙二醇等兩種含OH基之醇類添加物，利用噴霧熱裂解法製備SrTiO3粉體，以X光繞射分析儀(XRD)、場發射掃描式電子顯微鏡(FE-SEM)、場發射穿透式電子顯微鏡(FE-TEM)、氮氣吸/脫附分析儀(BET)、背向散射電子繞射儀(EBSD)等儀器分別研究粉體與塊材之相鑑定、粒子表面型態與其內部晶體形貌、比表面積、晶粒取向與晶界分析等。另，以阿基米得(Archimedes)浮力原理分析塊材之相對密度，續利用恆電位恆電流儀量測其阻抗值，進而計算分析導電度。
由實驗結果得知，前驅物添加硝酸及含OH基的不同醇類添加物所製備之SrTiO3粉體，經生胚製程與高溫燒結後，皆較前驅物添加硝酸所製備之塊材擁有較高Σ3共位晶界所佔比例和較高導電度。

Strontium titanate (SrTiO3) is one of the anode candidates for solid oxide fuel cell (SOFC) applications due to its crucial properties inclusive of high thermal and chemical stability, and mixed ionic and electric conduction behavior. The early studies reported that hydroxyl (OH) groups manipulate the shape of SrTiO3 surface; furthermore, they can control the crystal growth by changing the surface energy. This concept may be used to increase the population of (111) surfaces, and then more (111) surfaces form more Σ3 grain boundaries which have the lower energy for high ionic conductvity. In this study, the two common OH addtives of glycerol and 1,2-Propanediol were used to prepare the starting powders of SrTiO3. SrTiO3 powders were synthesized by ultrasonic spray pyrolysis and then sintered to form polycrystalline SrTiO3. Characterizations for SrTiO3 including the Archimedes method, X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), field-emission transmission electron microscopy (FE-TEM), Brunauer-emmett-teller (BET) and the electrochemical impendence spectroscopy method (EIS) were required to observe the density, phase composition, particle morphology, specific surface area, and conductivity, respectively. Also, the grain boundaries orientations were characterized by electron back-scattered diffraction (EBSD). The experimental results show that the specimens of additive-treated SrTiO3 powders have higher population of (111) planes and exhibit higher conductivity than un-treated one. In addition, the highest population of Σ3 grain boundaries is generated by 1,2-Propanediol treatment (11.0  0.8%) SrTiO3 and followed by glycerol treatment (10.0  0.3%) and pure treatment (2.5  0.2%), respectively.

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