臺灣博碩士論文加值系統

本研究利用化學水浴法 (chemical bath deposition)在玻璃上成長氧化鋅奈米棒(ZNR)，藉由聚乙烯亞胺(polyethylenimine , PEI)阻礙ZNR的側面生長，以及光化學沉積銀金屬於ZNR表面，獲得高長徑比(aspect ratio)與高催化活性的ZNR陣列薄膜。我們以X射線繞射光譜儀(XRD)、掃描式電子顯微鏡(SEM)、紫外線-可見光光譜儀(UV-vis)、原子吸收光譜儀(AA)等鑑定其特性。光催化反應是將ZNR 陣列薄膜置於128 W、λmax=300 nm的光反應器內，照光降解10 mg/L亞甲基藍溶液，作為評估ZNR 陣列薄膜光催化的活性。光分解水反應是利用100 W Xe arc lamp照射浸於電解液1M KOH中的工作電極上，測量其光轉換效率。
實驗結果發現，隨著製備時間由5小時增長至20小時，ZNR的長度由3.3 μm 增加至12.4 μm，同時，直徑由100 nm增加至400 nm，長徑比約為34。在加入PEI後，製得的ZNR長徑比提高至60左右。以亞甲基藍脫色反應作為光催化活性評估。當ZNR的長度為10μm時，其光催化活性高於同厚度下的氧化鋅奈米顆粒(ZNP)薄膜。透過添加PEI和適量Ag修飾，獲得較高催化活性觸媒。此觸媒在光分解水反應中，也具有較佳光轉換效率及入射單色光子-電流轉化效率(IPCE)。

Zinc oxide nanorods (ZNR) on substrate were prepared in this study by chemical bath deposition method. In order to obtain ZNR of high aspect ratio and high photocatalytic activity of ZNR, we added polyethylenimine (PEI) and Ag were added. PEI was used to hinder the lateral growth of the nanorods. All the catalysts prepared in this study were characterized by XRD, SEM, UV-vis, and AA. The photocatalytic activity of ZNR arrays was measured by photobleaching of 10 mg/L methylene blue, in a photo-reactor equipped with a light of 128 W and λmax=300 nm. The efficiency of photoconversion of ZNR was evaluated by 100 W Xe arc lamp illuminating the work-electrode in 1 M KOH solution.
As the synthesis time increased from 5 to 20 hours, the results showed that, the length of the ZNR increased from 3.3μm to 12.4μm , the diameter increased from 100 nm to 400 nm, the average aspect ratio was about 34. Adding PEI to the synthesis solution would increase the aspect ratio to 60. For ZNR of 10μm length, the photobleaching activity of ZNR prepared with the addition of PEI is higher than that of zinc oxide nanoparticles film (ZNP). The most active photocatalytic catalyst was prepared by adding PEI in the synthesis solution and with the incorporation of Ag. The same catalyst also had the highest efficiency of photoconversion and incident monochromatic photo-to-current conversion in water splitting reaction.

中文摘要 Ⅰ
英文摘要 Ⅱ
誌謝 Ⅲ
目錄 Ⅳ
表目錄 Ⅵ
圖目錄 Ⅶ
第一章 緒論 1
第二章 文獻回顧 2
2.1 氧化鋅簡介 2
2.2 氧化鋅奈米棒 2
2.2.1 氣相法 2
2.2.2 液相法 3
2.3 光催化 8
2.3.1 基本原理 8
2.3.2 氧化鋅擔體觸媒 11
2.4 水分解反應 13
第三章 實驗 16
3.1 藥品及儀器 16
3.2 觸媒製備 18
3.2.1 氧化鋅奈米粒薄膜 18
3.2.2 氧化鋅奈米棒 18
3.2.3 氧化鋅奈米棒擔體觸媒 19
3.3 觸媒特性分析 20
3.3.1 掃瞄式電子顯微鏡(SEM) 20
3.3.2 X-射線繞射光譜(XRD) 21
3.3.3 紫外光-可見光吸收光譜儀(UV-vis) 21
3.3.4 原子吸收光譜儀(AA) 22
3.4 亞甲基藍脫色反應 23
3.5 水分解反應 24
第四章 結果與討論 30
4.1 特性鑑定 30
4.1.1 X-射線繞射光譜(XRD) 30
4.1.2 紫外光-可見光吸收光譜儀(UV-vis) 32
4.1.3 掃瞄式電子顯微鏡(SEM) 35
4.1.4 原子吸收光譜儀(AA) 39
4.2 亞甲基藍脫色反應 40
4.2.1 ZNP 41
4.2.2 ZNR 43
4.2.3 ZNR-p 46
4.2.4 Ag/ZNR-p15 49
4.3 水分解反應 54
4.3.1 ZNP 54
4.3.2 ZNR 58
4.3.3 ZNR-p 63
4.3.4 Ag/ZNR-p15 67
第五章 結論 74

參考文獻 75
附錄
A Ag標準溶液校正曲線 78

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