現代光電元件，尤其是在特殊領域的諸如電子皮膚，智慧穿戴和
機器人皮膚等智慧元件呼籲新一代柔性透明電極的發展。
在本文中，我們在沒有添加任何外部封端劑的情況下以一種快速
便捷環保的凡爾尼置換法合成了一種長度超過1cm 的超長奈米銀線。
此外，受仿生結構的啟發，我們發展了一種以葉脈協助幹法轉印的技
術組裝我們合成的銀線將其排列成像葉脈一樣的形狀來用作透明電
極。歸因於葉脈結構的不斷進化以期獲得營養傳輸和吸收陽光之間的
平衡，我們的葉脈狀銀線網路透明度高達95%而與此同時片電阻只有
5Ω/sq，此外還獲得了很好的機械特性。以仿生的概念製造透明電極
的過程十分迅速，低廉，綠色的，適合大面積生產具有優異光電效果
的電極。
最後重中之重，為了證明我們電極的有效性，我們用銀奈米線電
極通過整合一個柔性奈米發電機和一個柔性電致變色元件建立了一
款變色龍仿生的電子皮膚，比較得出使用我們的電極比傳統的ITO 電
極組裝的元件需要的反應時間更短（2.9s）。值得一提的是，通過人
體的活動和元件顏色變化的互動效應，這款電子皮膚可以用來表演川
劇變臉（在表演中快速連續地變更臉譜來展示不同的心情和感受），
同時視覺化地監測人體的生理健康。重要的是這款臉譜可以讓我們每
個人都能以簡單有趣的方式感受川劇變臉而傳統的方式卻需要專門
的人受專門的訓練來表演。
總之，我們以仿生的方式，簡單的方法通過多功能重點突出奈米
科技在健康護理和藝術活動中的重要作用完成了一項具有創新性和
深遠意義的工作

Modern optoelectronics, especially smart devices in unique fields like electronic skins, wearable electronics and robotic skins call for development of new flexible transparent electrodes (TEs).
In the present work, we synthesized ultra-long silver nanowires over 1 cm through a relatively fast, environmental friendly and facile galvanic displacement method without adding external capping agent. In addition,
inspired by biostructures, we developed a facile leaf venation (LV)-assisted dry transfer printing technique to fabricate the transparent electrodes with silver nanowires, assembling silver nanowires into LV-like network. The LV-like network of ultra-long silver nanowires can help achieve a remarkable balance between transparency and conductivity (ultra-high transparency of 95% with ultra-low sheet resistance of 5 Ω/sq simultaneously),which is attributed to the ever-evolution of LV structure to obtain an optimized balance between transparency and transportation of nutrition, as well as excellent mechanical flexibility. The process of fabricating TEs with bio-inspired concept is fast, low-cost and green, which is suitable for large scale production with remarkable electro-optical performances.
The last but not least, A chameleon-inspired e-skin was established via integrating a transparent flexible triboelectric nanogenerator (TENG) with a flexible electrochromic device (ECD) using our Ag NWs electrodes to
demonstrate the effectiveness of our TE, which shows a significant shorter response time (2.9s) compared to that with traditional ITO. It should be noted that the smart e-skin could be used to replace special effect in the performance of Sichuan Opera named face changing (changing of masks in quick succession to show different emotions and feelings of the character in the play) through relative interactions between dynamical friction induced by body motions and color of e-skin, as well as monitor the health conditions visually. It is of great significance that the smart e-skin with our TE opens up a possibility for every person to experience traditional facechanging culture in a simple and interesting way. In contrast, the art normally takes a very skillful person to perform.
In a word, we completed a creatively profound work through
highlighting versatile applications of nanotechnology to heath care and artistic activity with bio-inspired concept through a relatively simple way

Acknowledgments…………………………………………………………………………………………………Ⅰ
Abstract……………………………………………………………………………………………………………………Ⅱ
Chapter 1.Introduction………………………………………………………………………………1
1-1 Motivation……………………………………………………………………………………………………1
1-2 Transparent Conductive Films……………………………………………………3
1-2-1 Indium Tin Oxide (ITO)………………………………………………………………4
1-2-2 Graphene and Nanotubes………………………………………………………………7
1-2-3 Metal Films………………………………………………………………………………………9
1-2-4 Silver Nanowires………………………………………………………………………………12
1-2-5 Assembly of Nanowires for TEs……………………………………………14
1-3 Electrochromic Devices (ECDs)……………………………………………….16
1-4 Triboelectric Nanogenerator (TENG)………………………………….18
Chapter 2. Experiment Procedures……………………………………………………20
2-1 Preparation of Ultra-long Silver Nanowires………………20
2-2 Substrate Preparation…………………………………………………………………… 20
2-3 Leaf Etching………………………………………………………………………………………………20
2-4 LV-assisted Dry Transfer Process…………………………………………21
2-5 Synthesis of Prussian Blue (PB) and Ni-PB Nanoparticles.……………………………………………………………………………………………………23
2-6 Fabrication of Flexible ECDs……………………………………………………24
2-7 Surface Modification on PET………………………………………………………24
2-8 Analyses…………………………………………………………………………………………………………25
2-8-1 Sheet Resistance Measurement………………………………………………25
2-8-2 X-Ray Diffractometor (XRD)……………………………………………………27
2-8-3 Scanning Electron Microscope………………………………………………27
2-8-4 Sample Preparation for Transmission Electron Microscopy Observation………………………………………………………………………………27
2-8-5 Transmission Electron Microscopy……………………………………28
2-8-6 Cyclic Voltammetry…………………………………………………………………………28
2-8-7 UV-visible Spectroelectrochemistry………………………………29
2-8-8 Measurements of Nanogenerator……………………………………………29
Chapter 3. Results and Discussion…………………………………………………30
3-1 Transparent Electrodes……………………………………………………………………30
3-1-1 Growth Mechanism of Silver Nanowires…………………………30
3-1-2 Record of Ultra-long Silver Nanowires’ Growth…32
3-1-3 SEM Analysis…………………………………………………………………………………………33
3-1-4 TEM Analysis…………………………………………………………………………………………33
3-1-5 LV-like Network of Silver Nanowires……………………………35
3-1-6 Advantages of Ultra-long Silver Nanowires……………37
3-1-7 Transparency Related to Densities of Nanowires…………………………………………………………………………………………………………………38
3-1-8 Electro-optical Performances of Silver Nanowires Network………………………………………………………………………………………………………………………39
3-2 Triboelectric Nanogenerator………………………………………………………44
3-3 Smart E-skin………………………………………………………………………………………………45
3-3-1 Illustration of E-skin………………………………………………………………45
3-3-2 Analysis of E-skin…………………………………………………………………………46
Chapter 4 Summary and Conclusions…………………………………………………50
Chapter 5 Future Prospects……………………………………………………………………54
5-1 Combine 3D Graphene with Silver Nanowires…………………54
5-2 Utilization of Leaf…………………………………………………………………56
5-3 Combination with LB Techniques……………………………………57
5-4 W18O49 for ECDs……………………………………………………………………………58
References………………………………………………………………………………………………………………61

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