何國川臺灣大學：化學工程學研究所廖俊豪Liao, Chun-HaoChun-HaoLiao2007-11-262018-06-282007-11-262018-06-282006http://ntur.lib.ntu.edu.tw//handle/246246/52381本論文研究的電致色變材料選定為氧化著色的普魯士藍(Prussian Blue, PB)以及還原著色的poly(3,4-alkylenedioxythiophene)(PEDOT)，在搭配以碳酸丙烯(Propylene carbonate, PC)為溶劑的電解液後，可組成一PEDOT-PB互補式電致色變元件，其顏色變化上可由幾乎透明的淡藍色轉為深藍色。研究內容主要針對PEDOT薄膜、PB薄膜與PEDOT-PB元件在室溫與70℃下的穩定性進行一系列有系統的探討與分析，而離子進出PB薄膜與PEDOT薄膜的行為同樣也是研究的重點。最後，將藉由量測元件在室溫與70℃下的兩極電位分布，對元件長期連續操作穩定性的變化趨勢提出可能的解釋。 對於單極薄膜而言，我們評估了PB薄膜與PEDOT薄膜在70℃下0.1 M LiClO4/PC溶液中的熱穩定性，得知此兩薄膜皆具良好的靜態熱穩定性，研判影響PB薄膜與PEDOT薄膜在70℃下0.1 M LiClO4/PC溶液中之穩定性優劣的關鍵為連續操作穩定性。此外，我們提出當PB薄膜在0.1 M LiClO4/PC溶液中由PB態還原成普魯士白(Prussian White, PW)狀態時，會有部分Li+卡在晶格內的現象產生，使得部份PW態無法氧化回PB態進而導致PB的著色態穿透度呈現隨操作次數增加而衰退的趨勢。在以EQCM分析離子進出PEDOT薄膜方面，得知PEDOT在中性態與摻雜態(p-type)之間進行氧化還原時，薄膜內的電中性是由陰陽離子共同貢獻的。在室溫下0.1 M LiClO4/PC溶液中，Li+是維持薄膜電中性的主要離子，而在室溫下0.1 M TBAClO4/PC溶液中，維持薄膜電中性的主要離子則改變為ClO4-。另外，我們更進一步地提出PEDOT薄膜的氧化還原方程式並計算出陰陽離子的計量係數。 根據PEDOT-PB元件在70℃下的靜態熱穩定性與長期連續操作熱穩定性的評估結果，可判定元件在70℃的存放溫度下相當穩定，需要注意的應該是元件在70℃下的連續操作熱穩定性。此外，藉由比較元件在室溫與70℃下的長期連續操作穩定性可更清楚得知70℃主要是扮演加速元件因連續操作而衰退的角色。在著去色電壓的選擇上，不論在室溫或是70℃下，以-1.2 V為著色電位及0.6 V為去色電位，可得到較佳的穿透度變化值與穩定性。在室溫下，以階梯電位法連續操作10,000圈後，元件的穿透度變化仍維持最大穿透度變化的95.8%；當在70℃下連續操作10,000圈後，元件的穿透度變化仍則保有最大穿透度變化的61.0%。最後，利用量測元件在室溫與70℃下的兩極電位分佈，可知兩極的電位飄移對於元件在室溫與70℃下的長期連續操作穩定性表現不容忽視，並可說明70℃如何扮演加速元件因連續操作而衰退的角色。In this work, the complementary electrochromic device (ECD) with a color change between nearly transparent light blue and deep blue was assembled by poly(3,4-alkylenedioxythiophene) (PEDOT) and Prussian blue (PB). For the preparation of the electrolyte, the solvent was propylene carbonate (PC) and the salt was LiClO4 or TBAClO4. The objective of this study is focused on the stabilities of PB and PEDOT thin films as well as the PEDOT-PB ECDs at R.T. and 70℃. The ion transport within the PEDOT and PB are also discussed. Furthermore, the potential distributions of PEDOT and PB within the ECDs were measured to explain the change of the transmittance responses in the ECDs with increasing cycle number. After evaluating thermal stabilities of the PEDOT and PB thin films in 0.1 M LiClO4/PC solution at 70℃, the results showed that both PEDOT and PB thin films had good at-rest thermal stabilities but worse cycling thermal stabilities than their at-rest thermal stabilities. Moreover, we proposed that when a PB thin film is switched from the PB state to the Prussian White (PW) state in 0.1 M LiClO4/PC solution, Li+ will be inserted into the lattice and some will be trapped. This phenomenon forbids some of the PW oxidizing to the PB state and causes the decay of the darkened transmittance with increasing cycle number. The EQCM analysis revealed that the electroneutrality of the PEDOT thin film was mantained by the transports of both cation and anion when PEDOT was cycled between its neutral state and p-type doping state. In LiClO4/PC solution, the charge compensation within the PEDOT thin film is dominated by Li+. However, in TBAClO4/PC solution, dominant ion for charge compensation is ClO4-. Furthermore, we proposed an equation to explain the redox process for PEDOT and calculated the corresponding stoichiomtric numbers. From the thermal stability test of PEDOT-PB ECD at 70℃, the results showed that the ECDs had good at-rest thermal stabilities but their cycling thermal stabilities were obviously worse than their at-rest thermal stability. The results revealed that 70℃ would accelerate the cycling instabilities of the ECDs. On the other hand, whether the ECDs were switched at R.T. or 70℃, applying -1.2 V for darkening and 0.6 V for bleaching could achieve better cycling stabilities and larger transmittance differences. When the ECD was cycled potentiostatically between -1.2 and 0.6 V for 10,000 cycles at R.T., the transmittance difference still remained 95.8% of the maximum value (ΔTMax). When cycled at 70℃, its remaining transmittance difference at 10,000th cycle decreased to 61.0% of ΔTMax. Finally, according to the potential distributions of PEDOT and PB thin films within the ECDs, we can explain the changes of the transmittance responses of the ECDs as a function of cycle number and also the reason why the cycling instabilities of the ECDs being accelerated at 70℃.中文摘要 I 英文摘要 III 誌謝 V 目錄 VII 表目錄 X 圖目錄 XII 符號說明 XXVII 第一章 緒論 1 1-1前言 1 1-2電致色變技術簡介 2 1-2-1電致色變技術之應用 2 1-2-2電致色變材料與元件類型 6 1-2-2-1電致色變材料 6 1-2-2-2電致色變元件之類型與結構 8 1-2-3電致色變元件發展之瓶頸 10 第二章 文獻回顧與研究目的 11 2-1 PEDOT之簡介 11 2-1-1 PEDOT之光電行為 12 2-1-2 PEDOT之熱穩定性 17 2-1-3 PEDOT在電致色變元件上的應用 20 2-2普魯士藍之簡介 24 2-2-1普魯士藍之光電行為 26 2-2-2普魯士藍之熱穩定性 31 2-2-3普魯士藍在電致色變元件上的應用 33 2-3溫度對電致色變元件之影響 35 2-3研究動機與目的 37 2-4研究架構 39 2-5研究系統結構 40 第三章 實驗部分 42 3-1儀器設備 42 3-2實驗藥品 43 3-3實驗方法 44 3-3-1導電玻璃之前處理 44 3-3-2藥品之前處理 44 3-3-3定電流析鍍普魯士藍薄膜 45 3-3-4定電位析鍍PEDOT 45 3-3-5 LiClO4/PC與TBAClO4/PC電解液之製備 46 3-3-6元件之組裝 46 3-4電化學特性分析 48 3-4-1薄膜電化學特性分析-三極式 48 3-4-2元件電化學特性分析-二極式 48 3-5 In-situ UV-VIS光譜分析 48 3-6熱穩定性分析 52 3-7離子進出電致色變薄膜分析 53 3-8元件之長期穩定性測試 56 3-8-1元件於室溫下之連續操作穩定性 56 3-8-2經熱儲存元件於室溫下之連續操作穩定性 56 3-8-3元件於70℃下之連續操作穩定性 57 3-8-4改變電解質對元件連續操作之穩定性 57 3-9薄膜於元件內之絕對電位量測 58 第四章 電致色變薄膜於室溫與70℃之光電特性與穩定性分析 60 4-1 PB於室溫與70℃之光電特性與穩定性分析 60 4-1-1 PB之循環伏安分析與光譜特性分析 61 4-1-2 PB於70℃之熱穩定性分析 71 4-1-3 PB連續操作穩定性機制探討 76 4-1-4 不同操作電位下之PB連續操作穩定性分析 87 4-2 PEDOT於室溫與70℃之光電特性與穩定性分析 99 4-2-1 PEDOT之循環伏安分析與光譜特性分析 99 4-2-2 PEDOT於70℃之熱穩定性分析 110 4-2-3不同操作電位下之PEDOT連續操作穩定性分析 117 4-3離子進出PEDOT薄膜之行為 124 4-3-1陽離子效應 125 4-3-2陰陽離子進出PEDOT薄膜之行為 131 4-3-3氧化還原方程式與離子進出PEDOT薄膜之可逆性 142 4-3-4在70℃下陰陽離子進出PEDOT薄膜之行為 149 第五章 電致色變元件於室溫與70℃之光電特性與穩定性分析 154 5-1元件於室溫與70℃之光電特性與穩定性分析 154 5-2元件於70℃之熱穩定性分析 159 5-3電解質混合比與元件長期連續操作穩定性 166 5-4不同操作電位下之元件長期連續操作穩定性分析 185 5-5元件長期連續操作穩定性與兩極電位分佈之關係 194 第六章 結論與建議 206 7-1 結論 206 7-2 建議 213 第七章 參考文獻 216 附錄A 參考電極Ag/Ag+之製備與校正 231 附錄B EQCM原始數據 2343703738 bytesapplication/pdfen-US電致色變元件EQCMpoly(3,4-alkylenedioxythiophene) (PEDOT)普魯士藍熱穩定性電位分佈Electrochromic devicePrussian blue (PB)thermal stabilitypotential distributionthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/52381/1/ntu-95-R93524026-1.pdf