近年來氧化鋅在光學、電性和感測方面的特殊性質受到廣泛的重視，尤其在奈米領域，高比表面積的結構增強了氧化鋅的感測效應。
本論文探討經由水溶液化學法，大量製備摻雜鋁原子的氧化鋅奈米牆狀結構。鋁基板對牆狀結構的成長具有很重要的影響，在其他的基板上，都只能觀察到奈米棒狀結構。而經由穿透式電子顯微鏡的觀察，確認了牆狀結構中鋁的原子百分比平均含量高達14 %。在製程中，透過控制玻璃基板上蒸鍍鋁薄膜的厚度及水溶液的反應時間，能夠有效的影響牆狀結構的高度。此外，經由調整水溶液中反應物的濃度、比例及反應的溫度，也能夠系統化控制奈米牆狀結構的密度，進而達到控制比表面積大小的目的。本研究並以二氧化氮氣體作為感測對象，展示了表面積對氣體感測的影響，並以奈米牆狀及奈米棒狀混合結構的感測元件，成功的展示出比棒狀結構更高的靈敏度，而且能長時間在高濃度的環境下，持續吸附氣體而不飽和，且同時將牆狀結構的偵測極限從100 ppm降低到1 ppm。
研究中針對一系列的退火溫度和時間影響，有詳細的探討。經由400 ℃兩小時的熱處理，能夠使材料中的原子重新排列成較完美的晶體結構。實驗證明，退火時間對結構中缺陷消除的影響較退火溫度更大，而高溫且長時間的熱處理最能夠有效的消除晶體結構中的缺陷。透過穿透式電子顯微鏡的觀察，能夠清楚發現晶粒尺寸的增加，以及缺陷的消除。

ZnO has been widely investigated for its unique properties and versatile applications. This study focuses on the controlled growth and the properties of Al-doped ZnO nanowalls prepared by aqueous chemical solution method.
Large area, well aligned Al-doped ZnO nanowalls were synthesized. The Al atoms are uniformly doped into ZnO nanowalls to an atomic concentration of about 14 % after 400 ℃ annealing for 2 hr. The unique nanowalls structure was only found on Al substrates. The height of the nanowalls can be controlled by adjusting the reaction time and the amount of Al source. The density was influenced by the growth temperature or the ratio and the concentration of the reactants. As a result, the surface area can be well controlled. The influences on the growth of Al-doped ZnO nanowalls at different annealing temperature and time were investigated. Al atoms in ZnO nanowalls become uniformly doped in the nanowalls with an increasing grain size after the heat treatment.
The gas sensing properties to NO2 were demonstrated in this work. A higher sensitivity for the denser structure was observed. A mixed structure of Al-doped ZnO nanowalls and pure ZnO nanorods was found to possess a lower detection limit than nanowalls and higher sensitivity than nanorods. In addition, the mixed structure was not saturated for absorption for 10 min in 100 ppm NO2 environment.

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