我們利用溶膠凝膠法在不同反應環境下合成二氧化鈦，在四異丙基鈦進行水解反應時，加入不同的溶液使得最後的產物有著不同的形貌，並利用此兩種不同形貌的樣品做各自的後處理，討論其光催化的效果。在第一個實驗中在水解反應時，我們配置了乙醇和氟化鈉水溶液的混合溶液，使得水解時存在著氟化鈉模版為四異丙基鈦前趨物成核及成長的優先位置，並且討論其後處理對光催化的影嚮。而在第二個實驗中，我們配置了乙醇和水的混合溶液，使得水解反應時以最小表面能的形貌，產生球狀的二氧化鈦，之後並利用氟化鈉水溶液進行水熱法反應，產生一空心球結構，並且有擁有 (001) 最佳光催化活性露面，表現出極佳的光催化效果。

We synthesize TiO2 by sol-gel process using TTIP in various solutions to manipulate the morphologies of the products. The photocatalytic performance of these powders were examined and discussed in detail. In the first experiment, NaF(aq) and ethanol were added as hydrolysis took place. The NaF precipitated in solution acted as a template on which precursor preferentially react.. In second experiment, we used water and ethanol to hydrolyze the alkoxide. We obtain sphere-like amorphous TiO2 because it has the least surface energy. Then, we use NaF solution to do hydrothermal reaction. We obtain hollow sphere and possess (001) plane which is the most active plane in anatase TiO2. We also discuss photocatalytic performance of these TiO2.

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