本研究利用鍚粉末作為鍚蒸氣的來源和散布在有350 nm厚氧化矽的矽基板上的250 nm奈米金粒子在高溫下反應，一步驟合成金-氧化鍚核殼奈米線。所得合成產物藉由X-ray繞射儀和具有能量散佈分析儀之穿透式電子鑑定其晶體結構、微結構及化學成分。為了研究其熱膨脹性為，使用臨場穿透式電子顯微鏡。初步發現，在250-750℃下，金(鍚)具有1.02×10-4 (1/K)的熱膨脹係數，而氧化鍚具有5.9×10-6 (1/K)的熱膨脹係數。因此，金(鍚)-氧化鍚核殼奈米線適合作為高溫奈米溫度計。另一方面，藉由金(鍚)之固液轉換溫度與金-鍚二元相圖可初步預測金(鍚)可能之組成，而後由高分辨電子顯微鏡鑑定其組成，最終建立一可能金(鍚)-氧化鍚核殼奈米線之可能成長模型。

In this study, a one-step approach is utilized to fabricate Au-SnO2 core-shell nanowires. 250 nm Au nanoparticles were dispersed on a Si substrate with 350 nm silica capping layer, Sn vapor was provided by Sn powders at elevated temperature. The crystal structure, microstructure, and the chemical composition of the as-grown products were examined by X-ray diffractometer (XRD), and field emission transmission electron microscopy (FETEM) attached with an energy dispersive spectrometer (EDS). To investigate the thermal behaviors of Au(Sn)-SnO2 core-shell nanowires, an in-situ TEM was used to observe the sequential reactions during the process of the nanowires. The Au(Sn) core has a thermal expansion coefficient of 1.02×10-4 (1/K), and the coefficient of thermal expansion of SnO2 shell is 5.9×10-6 (1/K) in the temperature region of 250-750℃. Hence, Au(Sn)-SnO2 core-shell nanowires can be good candidate of high temperature nanothermometers. On the other hand, a possible growth model of Au(Sn)-SnO2 core-shell nanowires can be proposed through the solid-liquid transition temperature of the Au(Sn) core and the Au-Sn binary phase diagram. The Au(Sn) core melted at the temperature region of 200-250℃, then the possible composition of the Au(Sn) core could be predicted by using the Au-Sn binary phase diagram. Finally, the exact composition of the Au(Sn) core were characterized by high resolution transmission electron microscopy (HRTEM).

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