氧化鎵奈米結構製備及氧化鎵奈米管作為奈米溫度計應用之研究

Synthesis of Ga2O3 Nanostructures and the Application of Au-filled Ga2O3 Nanotubes as Nanothermometer

龔南葳(Nan-Wei Gong)

指導教授 ： 陳力俊

國立清華大學/工學院/材料科學工程學系/碩士(2007年)

https://doi.org/10.6843/NTHU.2007.00366

摘要

本研究重點為一維氧化鎵奈米結構及金填充氧化鎵奈米管的製備。使用三區爐管並在氬氣氣氛下使用碳粉將氧化鎵粉末還原，升溫至1100℃後通入氧氣，在低溫區使用金作為觸媒的矽基板上成長氧化鎵的奈米結構。反應的低溫區，溫度設定為700-800℃，並且在高溫持溫反應，而反應的時間為1-2小時。利用不同的壓力控制，可以製備奈米線、奈米片狀結構、以及金填充的奈米管，而奈米結構的長度可由反應的時間來控制。奈米管、奈米線、奈米片狀結構的成長壓力分別為3-4 torr, 4-5 torr, 5-6 torr，其中奈米管中金的填充是由於金在奈米管中的毛細現象所造成，而金的填充與矽基板上的金觸媒厚度有正相關的關係，足夠的觸媒可以提供毛細現象的原料，達到完全填充的奈米管。使用本系統製備出的一維奈米結構，直徑分佈為50-100奈米(nm)，此外長度可以從1微米到數十個微米。利用穿透式電子顯微鏡進行臨場 (in situ) 加熱並觀察研究奈米尺度下，金填充的氧化鎵奈米管中的熱膨脹行為，我們發現從300 ℃到 800 ℃ 金呈現線性膨脹的行為，其中線性膨脹可以藉由與加熱溫度互相參照而計算出金填充的氧化鎵奈米管的熱膨脹與溫度的關係。由於氧化鎵和金都具有極穩定的熱與化學性質，該結構可以作為高溫之奈米溫度計，應用於奈米尺度特定區間的溫度量測。

關鍵字

氧化鎵 ； 奈米溫度計 ； 奈米管 ； 奈米結構

並列摘要

The synthesis and characterization of Ga2O3 nanowires, nanobelts, as well as Au-filled Ga2O3 nanotubes have been conducted. Ga2O3 nanotubes were fabricated by an effective one-step chemical vapor deposition (CVD) approach. Our approach is based on the physical evaporation of gallium oxide powder through vapor–liquid–solid, or vapor-solid mechanism and surface diffusion growth mechanism. The reaction is processed under Ar gas flow and after the Ga2O3 source powder was reduced by graphite, the introduction of O2 will then enable the growth of Ga2O3 nanostructures on Si (001) substrates. Different morphologies of 1-D Ga2O3 nanostructures are controlled via different pressure. The length nanostructures can be controlled by the reaction time.
For Au-filled Ga2O3 nanostructures, the gold interior was introduced by capillarity. Linear thermal expansion of Au within single crystalline Ga2O3 shell up to 800 ℃ was observed by in situ transmission electron microscopy. Since both Ga2O3 and Au possess excellent thermal and chemical stability, the structure can be used as a wide range high-temperature nanothermometer for localized region.

並列關鍵字

gallium oxide ； nanothermometer ； nanotubes ； nanostructures

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