開發中溫固態氧化物燃料電池關鍵材料之新穎製備方法研究

Development of Novel Methods for Preparing the Key Materials for Intermediate Temperature SOFC

吳家德(Jia-De Wu)

指導教授 ： 鄭淑芬

共同指導教授 ： 王錫福(Sea-Fue Wang)

國立臺灣大學/理學院/化學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201603490

摘要

本研究目的在針對中溫固態氧化物燃料電池之關鍵材料開發新穎製備方法，第一部分為以「中間相法」合成鈣鈦礦結構的鑭鍶鎵鎂氧化物 ( La1-xSrxGa1-yMgyO3-δ ，LSGM)，以應用作為中溫固態氧化物燃料電池之電解質材料，第二部份則以「電紡絲法」製備La1-xSrxCo1-yFeyO3 (LSCF)中溫固態氧化物燃料電池陰極。第一部分的研究中，將LSGM所需金屬元素分開來，先以Pechini法合成出LaGaO3、MgGa2O4兩種中間相，再添加其餘兩種金屬氧化物以固態反應法合成LSGM。可發現藉由LaGaO3中間相之二階段反應可在較低溫時獲得主相鈣鈦礦結構，且經由燒結後可有效去除二次相LaSrGa3O7。由MgGa2O4中間相之二階段反應法則需要燒結至1500 oC方能獲得鈣鈦礦結構的LSGM產物。第二部分的研究是以電紡絲法製作陰極層，此方法具有增加三相界面、提供連續的電荷傳遞路徑等優點，為了增加其效能本研究以電紡絲法直接噴於電解質面上製備陰極，尋找適合方法改善陰極和電解質接觸面不佳的問題。

關鍵字

固態氧化物燃料電池 ； 固態反應法 ； 鑭鍶鎵鎂氧化物 ； 鈣鈦礦結構

並列摘要

The purpose of this study is to investigate the key materials for intermediate temperature SOFC. In the first part of this study, an intermediate phase method was used to synthesize perovskite phase La1-xSrxGa1-yMgyO3-δ (LSGM), which is used as the electrolyte material of intermediate temperature SOFC. The second part is to prepare the La1-xSrxCo1-yFeyO3 (LSCF) cathode via electrospinning method. In the first part, the required elements were separated to synthesize the target material by two stages. The Pechini method was applied to prepare two types of intermediate phase LaGaO3 and MgGa2O4 in the first stage, and then the other two metal oxides were added by solid-state reaction method in the second stage. With the doubly-doping of the other two metal oxides, La1-xSrxGa1-yMgyO3-δ of desired perovskite phase can be obtained successfully. It was observed that La1-xSrxGa1-yMgyO3-δ of desired perovskite phase could be obtained at relatively lower temperatures via the two-stage reaction with LaGaO3 as the intermediate phase. On the other hand, the materials prepared from MgGa2O4 intermediate phase required sintering at 1500 oC to get the target perovskite phase. In the second part of this study, electrospinning method was applied to fabricate cathode coating on the electrolyte surface. It is known that electrospinning technique can increase TPB sites and continuous pathway for charge transfer. Here we tried to find out a proper method for improving the contact between cathode and electrolyte.

並列關鍵字

Solid oxide fuel cells ； solid-state reaction ； LSGM ； perovskite

參考文獻

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