奈米銀線之簡易製備法暨透明電極之應用

Facile Synthesis of Ag Nanowires for Transparent Conducting Electrodes

曾憲宏(Sian-Hong Tseng)

指導教授 ： 呂明諺

國立清華大學/工學院/材料科學工程學系/碩士(2019年)

摘要

本研究以伽凡尼法製備奈米銀線，探討不同製程參數（如銀離子濃度、反應溫度、銀離子來源及反應金屬種類等）對形貌之影響，根據實驗結果，當使用1 mM硝酸銀溶液並以釩作為反應金屬，在25 ℃下可合成出大量的奈米銀線。實驗過程分別以SEM及XRD鑑定產物之表面形貌及相結構，並以TEM及STEM進一步瞭解奈米銀線之微結構及缺陷狀況。
成功合成出大量銀線後，以滴塗法製備奈米銀線電極陣列，當奈米銀線塗佈濃度為248 mg·m-2時，其對550 nm之光穿透度可達90%。本研究進一步將之與同樣對光具有穿透度且擁有可撓性之二硫化鉬薄膜結合製作出大面積可撓式透明元件，由於使用多層的二硫化鉬薄膜，元件整體之穿透度下降至60%。
除了穿透度分析，本研究在元件受力彎曲之情況下進行電性量測，以理解元件陣列在不同彎曲程度及次數下之操作穩定性，結果顯示當對元件施予大應變量為0.5%的情況下，元件電流值變化量小於5%，另外當元件經過50000次0.33%應變量之彎曲循環後，電流值僅衰退約13%，展現了以伽凡尼法合成之奈米銀線作為可撓式透明電極之應用潛力。

關鍵字

奈米銀線 ； 透明導電薄膜

並列摘要

Silver nanowires (AgNWs) were synthesized by Galvanic replacement method in this study. The influences of experimental parameters, e.g., Ag+ concentration, reaction temperature, species of Ag+ source and donor metals, on the morphological changes of Ag nanostructures were investigated. As a result, large quantity of AgNWs is grown in 1 mM AgNO3 solution at room temperature with V foil, V foil serves as donor metal during the reaction, while Ag nanoparticles or dendrites were obtained in other cases.
AgNWs film were prepared by photolithography and drop-coating, the transmittance of which reaches up to approximately 90% at the wavelength of 550 nm as deposition density of AgNWs is 248 mg·m-2. To fabricate flexible transparent devices, multilayer MoS2 film was integrated with AgNWs electrodes, meanwhile the transmittance dropped to 60%.
The electrical measurements under bending were conducted to examine stability and durability of flexible transparent devices. The currents change less than 5% as 0.5% strain is applied onto the device. Furthermore, after bearing 50000 bending cycles under a strain of 0.33%, devices functioned normally with the attenuation of electrical current of merely about 13%, demonstrating the potential of AgNWs for the application of transparent flexible conducting film.

並列關鍵字

Silver Nanowire ； Transparent Conductive Film

參考文獻

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