2016-01-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/679969摘要：矽或矽鍺合金等材料應用於鋰離子二次電池的陽極時，可以提供非常高的能量密度，在充放電過程中，電極材料結構會因鋰離子的嵌入，使得體積膨脹約四倍之多，嚴重破壞原有的電極結構。但若以奈米結構、具備適當的孔隙率的矽鍺材料應用於電極，則可以解決前述體積膨脹的問題。現今常用的矽鍺奈米材料的製作，須藉由昂貴的高真空設備、及使用具有毒性的危險氣體等的化學氣相沉積方法以進行，為了讓以矽或是矽鍺為主體的材料更有效應用於二次電池的發展中，我們在本計畫嘗試開發更經濟的方法，已製作矽鍺奈米材料。我們將二氧化矽與鎂等地球上含量豐沛的材料，以熱還原反應製作矽與氧化鎂的複合式三維結構，而後再以酸蝕刻將氧化鎂去除，以形成矽為主的三維奈米結構。在實驗過程中，我們將以x光繞射分析、穿透式電子顯微鏡分析等技術進行反應條件與所形成結構的觀察。<br> Abstract: For the applications in lithium-based secondary batteries, silicon and silicon-germanium (SiGe) alloys are useful anode materials that exhibit high energy density. During the charge/discharge processes, these anode material swells four times due to the intercalation of the lithium ions. Thus, the battery structure is severely destroyed. Alternatively, if the Si or SiGe anode is in the nanostructured form with a suitable porosity, the swelling-induced battery damage can be avoided. The routinely used chemical vapour deposition method for the growth of Si or SiGe nanostructures rely on the use of expensive vacuum system and dangerous gas precursors. In order to practically apply Si or SiGe alloys for future development of lithium secondary batteries, we intend to develop an economic process to fabricate Si or SiGe nanomaterials. In this study, we use earth-abundant silicon oxide and magnesium powder as the raw materials. The powder of the two materials is mixed and annealed to form an Si and MgO composite. After etching away MgO in the composite, we can obtain Si-based three dimensional complex nanostructures for being the the anodes in lithium batteries. We use x-ray power diffraction and transmission electron microscopy to study the reactions and obtain the three dimensional structural information.矽矽鍺合金二次電池化學蝕刻法奈米結構穿透式電子顯微鏡分析Siliconsilicon germanium alloysecondary batterynanostructureschemical etchingtransmission electron microscopy