三氧化鎢/氧化鈦光電致色變奈米複合薄膜之製備與性質研究

A Study on the Preparation of Tungsten Trioxide/Titania Nanocomposite Thin Films and Their Photoelectrochromic Properties

陳彥文(Yan-Wen Chen)

指導教授 ： 林正嵐

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2012年)

https://doi.org/10.6846/TKU.2012.01083

摘要

本研究以溶膠-凝膠法搭配旋轉塗佈法，於FTO導電玻璃上製備出三氧化鎢-氧化鈦奈米複合薄膜及純三氧化鎢薄膜。改變三氧化鎢-氧化鈦奈米複合薄膜之鎢、鈦莫耳比，利用SEM、XRD、定電流定電位分析儀與紫外/可見光光譜儀來對薄膜作表面微結構、晶體結構、電化學、變色響應時間、薄膜穩定性及穿透率光譜等分析，找出擁有最佳電致色變效果之複合薄膜莫耳組成比。實驗結果顯示，當鎢、鈦莫耳比為 70 : 30 時，其薄膜具有均勻透明的非晶形結構、最佳入射光調節能力 (△T = 58 % @ 550 nm) 及電化學穩定性。薄膜於 650 nm 波長之著色/去色時間為 34 s / 20 s，著色效率為37 cm2/C。
於三氧化鎢-氧化鈦奈米複合薄膜上塗佈二氧化鈦薄膜作為光電子提供者，形成具光電致色變性質的複合薄膜。將三氧化鎢-氧化鈦/二氧化鈦雙層薄膜結合濺鍍白金之ITO對電極，以含有0.5M碘化鋰之液態電解質封裝成光電致色變元件，並對元件做光電致色變性質分析。在無外加電場操作的情況下，將光電致色變元件於紫外光照射下進行著色，於短路狀態進行去色。實驗結果顯示，使用WTiB-30 / TiO2薄膜比使用WO3 / TiO2薄膜的元件有較好的光調節能力 (△TWTiB-30/TiO2 = 36.6 % , 64.3 ~ 27.7，△TWO3/TiO2= 33.1 % , 59.6 ~ 26.5)。

關鍵字

三氧化鎢 ； 氧化鈦 ； 複合薄膜 ； 電致色變 ； 光電致色變

並列摘要

A sol-gel derived peroxotungstic acid (PTA) sol has been employed for the deposition of tungsten trioxide-titania nanocomposite (WO3-TiOx) thin films and pure tungsten trioxide (WO3) thin films on fluorine doped-tin oxide (FTO) conductive glass by spin coating technique. As changing the molar ratio of W to Ti, we can observe different properties. By using scanning electron microscopy (SEM) and X-ray diffraction (XRD), we can know micro-structure and crystalline structure of composite films respectively. In electrochemistry aspect, using Potentiostat/Galvanostat to get response time, stability and quantity. And optical properties observed by UV/Visible, like overall wavelength scanning and transmittance spectrum. Besides, we find the optimum component for the ratio of W to Ti. The results show that when the molar ratio of W to Ti is 70 to 30 (WTiB-30), the film has uniform and transparent surface and the structure reveals amorphous phase. There is the best electrochemical stability and transmittance modulation (△ T = 58% @ 550 nm) in this condition. At 650nm irradiation, the coloring and bleaching time of the film are 34 s and 20 s, and the coloration efficiency is 37 cm2/C.
Coating titanium dioxide (TiO2) film on the WO3-TiOx thin films as optoelectronics provider, and then forming photoelectrochromic (PEC) composite films. The PEC device form the order is glass/FTO/WO3-TiOx/TiO2/electrolyte/Pt/ITO/glass and fabricated by the following process : two coated substrates assembled together with hot-melt spacers and they are separated by an electrolyte. As liquid electrolyte, 0.5 M LiI dissolved in propylene carbonate (PC) is used. When no applying external voltage, the PEC device is coloring in UV illumination, and bleaching in short circuit. Experimental results show that, using WTiB-30/TiO2 film of the PEC device has higher transmittance modulation than WO3/TiO2 film (△TWTiB-30/TiO2 = 36.6 %, 64.3 ~ 27.7，△TWO3/TiO2= 33.1 %, 59.6 ~ 26.5).

並列關鍵字

tungsten oxide ； titanium dioxide ； composite films ； electrochromic ； photoelectrochromic

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