摘要
透明導電薄膜廣泛的被應用於太陽能電池、發光元件、觸碰螢幕等消費性電子產品之中，而傳統的透明導電薄膜材料銦錫氧化物(ITO)由於其易碎的性質，無法滿足未來軟性電子產品的應用需求，在軟性透明電極材料之中，因為銀奈米線可配合濕式製程與卷對卷(Roll to roll)製程整合，進行大面積連續的製造以降低成本，以及銀奈米線電極優秀的導電潛力，本研究以銀奈米線作為透明電極薄膜材料並應用於有機太陽電池之上。
本研究提出在保有滾印製程優勢下，藉由調整製程參數以及銀奈米線溶液性質，達到排列以及成束銀奈米線的動作。在滾印過程之中，銀奈米線濕膜因為熱對流關係將銀奈米線帶往乾燥破洞的兩旁，當熱對流停止後，濕膜則因為表面張力持續擠壓銀奈米線，同時滾印方向產生的牽引力將濕膜破洞沿滾印方向拉扯，藉此將銀奈米線成束並且排列。傳統滾印隨機分布的銀奈米線電極，透光度導電度約為14.9 Ω sq-1以及89.8%，電性均勻度CV值則為0.63%，且在膠帶以及彎折測試之中，電極被破壞致使片電阻值明顯的上升。排列銀奈米線束電極在透光度89.4%的情況下展現出5.88 Ω sq-1的超低片電阻值，除此之外，本研究中以正交的鋪設方法實現均勻度CV值0.1%;而在電極的安定性部分，銀奈米線束電極可在室溫中存放30天以上不影響其導電效能;另外以膠帶反覆沾黏100次後電阻值只略上升至原先的103%，展現了成束排列銀奈米線電極對基材穩固的沾附性;在彎折測試中，成束排列的銀奈米線可在半徑1 mm下彎折3000次而片電阻值僅上升至108%。在保有滾印製程優勢下，本研究成功藉由成束以及排列銀奈米線大幅的提升了電極的表現。
本研究建立了滾印排列銀奈米線束製程模型，完整描述熱對流以及表面張力作用造成的濕膜破洞大小，並進一步擠壓銀奈米線成束排列，該模型可利用於未來在不同表面性質基材鋪設。本研究以創新滾印製程配合超高徑長比銀奈米線，研製出高效能方向性成束銀奈米線電極，並配合鋪設導電高分子PEDOT:PSS作為電洞傳輸層，並以P3HT:PCBM作為主動層製作，軟性有機薄膜太陽能電池，達成效率1.84%，而ITO製作出之太陽能電池效率則為2.01%，其效率已達ITO電極有機太陽能電池91%。

Abstract
Roller assisted, coated, and silver nanowire (AgNW) based transparent conductive film exhibits promising potential for industrial-scale manufacturing, flexible, and light-weight electronics such as solar cells, touch panel, and wearable sensors. Efforts have been made to overcome the disadvantages of AgNW based transparent conductive film through encapsulating functional materials. For instance, graphene or metal oxide encapsulating on AgNW network to insulate and strengthen AgNW network and minimize junction resistance between AgNWs. However, the random distributed-AgNW network under functional materials is not yet to be optimized. In this work, we demonstrate aligned-AgNW-bundles network via adjusting operating conditions of roll coating process. The aligned-AgNW-bundles network coated on PET substrate is then immersing into water to remove PVP (Polyvinylpyrrolidone) residual and pressed to smooth the surface. Highly aligned and bundled AgNW network results in superior optoelectronic properties (sheet resistance 5.88Ω sq−1 at transmittance 89.4 %. Also, remarkable adhesion to the substrate, electric uniformity, mechanical properties, and stability under heat stress are shown in this work. As for the electric uniformity, owing to the alignment of AgNW, the coefficient of variance of aligned-AgNW-bundles is 0.19% comparing to the electric uniformity of random-distributed-AgNW network 0.63%. Aligned-AgNW-bundles network is able to maintain conductivity even under 100 times 3 M scotch tape peeling cycles. The sheet resistance of aligned-AgNW-bundles network increase to 103% after peeling cycles which is much more secure than random-distributed-AgNW network (290%). Furthermore, the sheet resistance of aligned-AgNW-bundles network after 30 days storage in room temperature condition slightly increases to 113%. As for the mechanical properties, aligned-AgNW-bundles network can sustain 1 mm radius bending 3000 times and even maintain conductive during 7 times folding.
In this work, I demonstrate well-perform AgNW network through synthesizing AgNW with ultra-high aspect ratio and optimizing roll coating process. Followed with coating process, I build up a model to depict the formation of aligned-AgNW-bundles network during coating process. With the factors of surface tension and evaporation, the model can precisely predict the hollow sizes of wetting film and further to calculate the alignment of AgNW. In the end of this work, the PEDOT:PSS is coated on aligned-AgNW-bundles network. P3HT:PCBM is then spin coated on PEDOT:PSS as active layer of organic solar cell. The efficiency of aligned-AgNW-bundles network based solar cell can exceed 1.84% comparing to ITO based solar cell 2.01%.

目錄

摘要1
Abstract3
目錄6
圖目錄8
表目錄.12
第一章 緒論13
1.1 傳統透明電極薄膜13
1.2 軟性透明電極薄膜15
1.2.1 金屬網格透明電極薄膜17
1.2.2 導電高分子透明電極薄膜18
1.2.3 石墨烯透明電極薄膜20
1.2.4 奈米碳管透明電極薄膜21
1.2.5 金屬奈米線透明電極薄膜22
1.2.6 軟性透明電極薄膜材料總結24
1.3 銀奈米線透明電極薄膜之瓶頸27
1.3.1 銀奈米線合成以及尺寸影響27
1.3.2 銀奈米線接觸電阻消除30
1.3.3 銀奈米線電極表面粗糙度降低34
1.3.4 銀奈米線電極均勻度提升35
1.3.5 銀奈米線電極沾附性提升37
1.3.6 銀奈米線電極安定性提升39
1.4 複合式銀奈米線軟性透明電極薄膜40
1.5 排列銀奈米線電極.43
1.6 研究動機44
1.7 研究目的與方法45
1.8 論文架構48
第二章 實驗系統與材料48
2.1 滾印系統48
2.2 銀奈米線合成系統與材料50
2.3 基材選用51
第三章 超高徑長比銀奈米線合成方法52
3.1 超高徑長比銀奈米線銀奈米線53
3.2 銀奈米線合成與純化54
3.3 銀奈米線合成加熱溫度及時間影響57

第四章 滾印成束排列銀奈米線62
4.1 滾印製程原理介紹及卷對卷製程近況優勢介紹62
4.1.1 滾印製程原理介紹62
4.1.2 卷對卷滾印製程近況及優勢64
4.2 滾印成束排列銀奈米線透明電極薄膜.66
4.2.1 滾印成束排列銀奈米線電極原理66
4.2.2 滾印成束排列銀奈米線製程步驟84
4.2.3 成束排列銀奈米線排列方向性探討88
4.3 成束排列銀奈米線電極後處理93
4.3.1 水浴法去除高分子分散劑包覆層93
4.3.2 熱壓降低表面粗糙以及銀奈米線接觸點融合96
4.4 結果與討論99
第五章 成束排列銀奈米線電極特性100
5.1 成束排列銀奈米線電極透光及導電度量測100
5.2 成束排列銀奈米線電極均勻度量測104
5.3 成束排列銀奈米線電極沾粘性量測106
5.4 成束排列銀奈米線電極表面粗糙度量測108
5.5 成束排列銀奈米線電極熱疲勞測試111
5.6 成束排列銀奈米線電極安定性測試112
5.7 成束排列銀奈米線電極撓性測試114
5.8 成束排列銀奈米線焦耳壓力測試116
5.9 結論與討論118
第六章 有機太陽電池應用122
6.1 有機太陽能電池簡介122
6.2 有機太陽能電池結構與設計123
6.3 有機太陽能電池製程方法125
6.4 有機太陽能電池製作參數探討128
6.5 有機太陽能電池效能132
第七章 結論134
7.1 研究結論134
7.2 研究成果135
7.3 學術貢獻與技術創新138
7.4 未來工作145
參考文獻147

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