本研究主要利用靜電紡絲製備異價離子共摻雜之氧化鈰(Ce0.78Gd0.2Sr0.02O2-δ，以下簡稱GDCSr纖維，藉由改變高分子載體濃度、電場強度與不同收集方式得到不同型態的收集物。實驗結果顯示，以轉軸收集器、注射馬達速率1.5ml/hr、電壓20kV、負極與針頭距離12cm、PVP濃度為整體溶液的11.32wt%，可得到直徑均勻和規則排列的100nm左右GDCSr纖維。實驗中利用X光繞射儀、掃描式電子顯微鏡、穿透式電子顯微鏡分析GDCSr纖維於不同燒結溫度(800 ℃、1000 ℃、1300 ℃、1500 ℃)之成相性、晶粒尺寸與結晶性。隨著溫度上升，GDCSr纖維內部晶粒也隨著成長，若燒結溫度超過1300 ℃則會破壞GDCSr纖維原始形貌，這顯示了GDCSr纖維陽極燒結溫度必須低於1300 ℃。
將製備GDCSr纖維應用於固態氧化物燃料電池(Solid Oxide Fuel Cell，SOFC)的陽極部分。GDCSr纖維經配製膠體後網印在GDCSr電解質上經高溫去高分子而形成網狀氧離子通路，再以浸鍍法使Ni粒子披覆於網狀氧離子通路上，然後用不同溫度燒結(1000 ℃、1200 ℃、1300 ℃)形成陽極。
陽極網印於GDCSr電解質(厚度0.7mm)並與白金參考電極之半電池，使用燃料氣氛15%H2(Dry,100cc/min)下在400~550 ℃之間，測量AC交流阻抗、鐵弗曲線、半電池之功率密度。
AC交流阻抗於1000 ℃/1hr、1200 ℃/1hr與1300 ℃/1hr三種燒結溫度參數顯示，1200 ℃/1hr陽極燒結溫度在各工作溫度(400~550 ℃)有較低的電極阻抗，經由阻抗值換算陽極活化能亦顯示1200 ℃/1hr燒結有最低陽極活化能(0.86 eV)。鐵弗曲線於各工作溫度下也顯示陽極燒結溫度1200 ℃時，交換電流密度(Io)值最高，同時也有最高功率密度(550 ℃，10.06 mW/cm2)。
另外，經由SEM得知，1200 ℃/1hr陽極燒結溫度，陽極與電解質接合良好且因為燒結溫度較低，使得鎳不易因高溫團聚而降低三相點區域，因此有較高的催化活性，進而得到較低的極化電阻、較高的交換電流密度及功率密度。
最後，利用靜電紡絲法製備GDCSr纖維應用於固態氧化物燃料電池(Solid Oxide Fuel Cell，SOFC)陽極時，發現在高溫及低氧分壓下，其工作溫度無法超越550 ℃及工作效率會下降。由SEM微觀影像發現，GDCSr材料於燃料20%H2(Dry,100cc/min)氣氛下600 ℃持溫2小時還原後，明顯晶粒成長，及TEM顯示以高分辨電鏡影像HRTEM)和相同zone axis = [001]逆傅立葉轉換，觀察其微觀區域，GDCSr還原後晶格扭曲和缺陷差排尺寸大小明顯較未還原GDCSr大且多。由於高溫低氧分壓時，氧化鈰變得非常不穩定，Ce3+的離子取代Ce4+，產生電子缺陷被所形成的離子氧空缺所補償，造成過多氧空缺。空缺越多，元素擴散越易，故晶粒容易成長。Ce4+易還原成Ce3+，Ce4+和Ce3+離子半徑差異大，易造成晶格扭曲及差排變多，使得氧離子傳導反而降低，影響整體發電效率。

Ni-Ce0.78Gd0.2Sr0.02O2-δ anode materials, having high ionic conductivity GDCSr fibers and fine Ni particles, sintered at different temperatures were developed for intermediate temperature solid oxide fuel cell application. Electrospinning deposition technique was adopted to produce nano sized GDCSr fibers using PVP as solvent material. Viscosity of the solution and the applied voltage played a significant role to generate long and uniform size fibers. The flow rate of 1.5 litre/h and voltage of 20 kV were maintained throughout the experiment. Fibers of average size of 100nm were generated using a collector placed at a distance of 12 cm. XRD of the GDCSr fiber sintered at different temperatures revealed in cubic phase. Scanning electron micrographs indicate that the size and length of fiber increase with increasing the sintering temperature. The existence of cubic structure and formation of uniform size fibers was confirmed by bright field image and diffraction patterns of transmission electron microscopy. The mixture of fiber and powder at weight of 75:25 was used to screen print on the GDCSr electrolyte. The anode films were prepared via a nickel wet dipping process and sintered at different temperatures. The micrograph of the anode sintered at 1200 ℃/1hr has a well defined microstructure in terms of electrolyte area covered with nickel and the triple phase boundary line between electrolyte, electrode and gas phase. Higher sintering temperature resulted in the formation agglomerates of nickel particles and crack in the films, which might be due to particle size of the initial powder.
Two important aspects for using fiber based anode, the kinetics of the hydrogen oxidation reaction and the effect of the microstructure on the electrochemical performance of the anode. Insight in these two aspects will lead to a better understanding and further improvement of the anode by changing the sintering temperature of the fiber based anode. For electrochemical characterization of the electrodes, impedance and tafel measurements are performed. Impedance measurements performed under standard conditions resulted in spectra, which when analyzed with an equivalent circuit, are built up of two semicircles and are found dominating with sintering temperature. The high frequency semicircle is ascribed to charge transfer phenomenon at the interface of anode and electrolyte and the low frequency semicircle is ascribed to the concentration polarization. The area specific resistance of around 28 -cm2 is observed at 550 ℃ for the anode sintered at 1200oC for 1hr. The significant reduction in overall electrode resistance in half cell with anode sintered at 1200 ℃/1hr can be attributed to an increased number of active sites. Moreover, the energy required to activate the electrochemical reaction is lower (0.86eV) in the anode sintered at 1200 ℃. The equivalent circuit constructed by fitting the Cole-Cole plots shows the deviation in the distribution of nickel particles and discontinuity of the interface between electrolyte and anode. Hydrogen oxidation reaction was estimated using tafel curves by calculating the exchange current density. Higher exchange current density of 5.2mA/cm2 was observed in the hall cell for the anode sintered at 1200oC/1hr at all working temperatures from 400 ℃ to 550 ℃. Half cells with fiber anode, bulk electrolyte and Pt cathode were developed. Half cell with anode sintering temperature of 1200 ℃/1h has shown better performance compared to other sintering temperatures, due to increase in triple phase boundary regions with long fiber anodes. The maximum power density of 10.02mW/cm2 is recorded in the voltage-current characteristic curves drawn at different temperatures. Transmission electron microscopy analysis was carried out to identify the reason for the reduce in reduction temperature (600 ℃/2hr) Electrolyte material after reduction has shown larger and higher number of dislocations compared to the electrolyte before reduction. SEM images have shown the difference in grain size. Grain size is found larger after reduction. XRD patterns reveal cubic phase in both materials. This was also confirmed from TEM diffraction pattern. The possible reason might be the addition of higher ionic radii elements such as Sr for Ce, enhances the lattice distortion and to compensate this lattice distortion dislocations are formed in the material. Moreover, the reduction of CeO2 to Ce2O3 has effected in increasing the dislocations in the material due to increase in electronic conductivity. The overall data indicates that the sintering temperature of the fiber anode has a significant effect on electrochemical performance of the half cell.

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