現今高科技產業日新月異及迅速蓬勃發展之時代，為因應發展所需，多元能源發展成為各界重視的議題之一。近年來由於全球環保意識抬頭、歐盟強勢主導綠色法規之下，故於開發新能源之時須將環保、綠能等要件納入考量。多元替代能源包括再生能源、燃料電池、核能發電等，其中又以燃料電池系統中之固態氧化物燃料電池最具發展潛力。固態氧化燃料電池是一種利用電化學反應的發電裝置，其不同於一般電池，不經燃燒過程，即可直接並高效率的將化學能轉換成電能，轉換過程中之產物亦較不會對環境造成威脅或破壞。
然而，轉換過程中經常伴隨著空氣與燃料氣體產生，為避免此現象發生進而獲得較高電力，內電極扮演著極重要的角色，而內電極須具備高電子導電率及高相對密度(≧94%)等兩大特質。早期文獻中提及，藉由固態反應法及Pechini法成功製備具高電子導電率和高相對密度之純La0.3Sr0.7TiO3，故於本研究中，選擇以鑭摻雜鈦酸鍶進行製備與分析。
實驗方法為使用硝酸鑭、硝酸鍶與異丙醇氧鈦作為前驅物，並添加不同濃度(0.29, 0.50, 1.16 and 2.33M)之醋酸和介面活性劑tritonX-100，利用噴霧熱裂解法製備鑭摻雜鈦酸鍶粉體，以X光繞射分析儀(XRD)、掃描式電子顯微鏡-電子能量散射圖譜(SEM-EDS)、穿透式電子顯微鏡(TEM)等儀器分別研究粉體與塊材之相鑑定及粒子表面型態等。另以阿基米得(Archimedes)浮力原理分析塊材之相對密度，再利用交流與直流阻抗分析儀量測其導電度。由實驗成果得知，藉由添加界面活性劑可成功使材料內部粒子進行重新並有序排列和堆積，進而有效提高相對密度和電子導電率。

Now that the world faced to the problem of exhausted energy, solid oxide fuel cells (SOFCs) have been remarkable for new generation energy. In order to collect the electricity and prevent air and fuel gases passing through, high electrical conductivity and relative density (≧94%) are required for SOFCs interconnector used to connect each cell. In this study, La-doped SrTiO3 which is one of expected candidate as SOFC material was synthesized. In particular, La0.3Sr0.7TiO3 was picked up because of providing higher electrical conductivity and relative density without second phase on based of previous study by solid state reaction (SSR) and Pechini method. La0.3Sr0.7TiO3 powders were prepared by SP method using different concentrations of acetic acid (0.29, 0.50, 1.16 and 2.33M) and were sintered for 5h at 1500℃ and 1600℃ without surfactants, and 1500℃ after mixing with surfactant of tritonX-100 while comparing with samples prepared by SSR and Pechini method. As characterization, X-ray diffraction (XRD), scanning electron microscopy – energy dispersive spectroscopy (SEM-EDS) and transmittance electron spectroscopy (TEM) were conducted to research crystallographic phase, particle surfaces morphology and particle inner structure respectively for powders. For bulks, XRD, SEM-EDS, Archimedes method and electrical measurement were conducted to research crystallographic phase, micrograph, relative density and electrical conductivity. It was confirmed that surfactant affected to increase relative density and electrical conductivity expectedly according to rearrangement of particles into ordered packing. Also, the particle morphology formation mechanism and indeterminate crystal generated on some of bulks were discussed.

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