新穎性氧化鋅奈米柱/導電高分子之奈米複合材料: 合成，特性及應用於壓電奈米元件之研究

Novel ZnO Nanorod/Conducting Polymer Nanocomposites: Synthesis, Characterization, and Applications in Piezoelectric Nanodevices

蕭智中(Chih-Chung Hsiao)

指導教授 ： 戴子安

國立臺灣大學/工學院/化學工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.10263

摘要

本研究利用濕式化學法以製備奈米柱氧化鋅/聚二氧乙基塞吩-聚苯胺共聚高分子之奈米複合材料。聚二氧乙基塞吩-聚苯胺共聚高分子是利用氧化聚合法聚合而成。氧化鋅奈米柱之製備則為運用水熱法來成長氧化鋅奈米柱於多種預鍍有氧化鋅種子層之基材上。不同基材上之氧化鋅種子層可藉由利用磁控射頻濺鍍氧化鋅薄膜或是旋轉塗佈自製的氧化鋅奈米顆粒之懸浮液這兩方式來製備於基材上。我們可以藉由調整成長氧化鋅奈米柱的製程參數以及基材表面粗糙度來控制所成長的氧化鋅奈米柱的形貌、結晶性、排列方向、成長速率、直徑、長度、成長數目及氧化鋅比表面積之大小。若使用未經退火處理的氧化鋅靶材所製備的氧化鋅種子層無結晶性，此種子層無法有助於成長規律性排列氧化鋅奈米柱於基材上。若使用經退火處理的氧化鋅靶材及施加120W以上之濺鍍功率，可得具有鐵鋅礦結構及沿[002]方向結晶的種子層，此有助於成長垂直排列及有六角柱狀的氧化鋅奈米柱。探討化學浴濃度對氧化鋅奈米柱之影響，發現在0.01M化學濃度下所成長的氧化鋅奈米柱能規則性且較分散的排列於基材上。而探討基材表面粗糙度對氧化鋅奈米柱之影響，發現表面粗糙度較小的ITO及PET薄膜基材上所成長的氧化鋅奈米柱之排列性與形狀均勻優於聚二氧乙基塞吩-聚苯胺共聚高分子薄膜基材上所成長的氧化鋅奈米柱。於本研究中，我們成功發展出一最佳製程能夠藉由化學浴法來成長垂直排列的氧化鋅陣列於多種預鍍有氧化鋅種子層的基材上。並藉由氧化鋅同時具有壓電及半導體兩性質，我們將氧化鋅/聚二氧乙基塞吩-聚苯胺共聚高分子之複合材料結合表面鍍有金之可撓PU薄膜當成上電極，製備成能夠以機械能轉換為電能的奈米發電元件。當施予一水平滾動力於上電極時，由氧化鋅/聚二氧乙基塞吩-聚苯胺共聚高分子之複合材料所製成的奈米元件可產生1nA/cm2之電流密度。

關鍵字

氧化鋅奈米柱 ； 聚二氧乙基塞吩-聚苯胺共聚高分子 ； 奈米複合材料 ； 濕式化學法 ； 磁控射頻濺鍍系統 ； 奈米元件

並列摘要

ZnO nanorods/ PEDOT-co-PANI copolymer nanocomposite materials have been synthesized via wet chemical method. The PEDOT-co-PANI copolymer film was prepared by using an oxidative chemical in situ polymerization method. ZnO nanorods on various substrates coated ZnO seed layer have been grown using an hydrothermal process. The ZnO seed layers were deposited by two methods, deposition of a thin film of ZnO particles through sputtering by using RF magnetron sputtering system and spin-coating as-prepared ZnO nanoparticles suspension. The change in morphology, crystallinity, orientation, growth rate, diameter, length, surface area per area and number of ZnO nanorods were controlled by modifying various process parameters and the surface roughness of substrates. It was observed that ZnO seed alyer with amorphous structure, prepared using ZnO target without annealing, didn’t facilitate the synthesis of well aligned ZnO nanorods in the solution grown process. Prior seeding of the various substrates by ZnO seed layer with good wurtzite structure and preferred orientation along the (002) direction, deposited using annealed ZnO target and up to 120W RF sputtering power, leads to nucleation sites onto which ZnO nanorods can be vertically oriented with respect to the substrate as hexagonal pillars with a flat facet surface on the tip. For the growth of ZnO nanorods in the chemical solution, the highly and separate aligned ZnO nanorod arrays can be grown on various ZnO-seeded substrates from 0.01M precursor concentrations, with a [Zn(NO3)]/[C6H12N4] ratio of 1. It was found that the morphology and alignment is strongly dependent on the surface roughness of substrate. The uniformity and alignment are well for the ZnO nanorods grown on the ZnO-seeded ITO and PET film substrates compared with ones on the two ZnO-seeded copolymer film substrates having an inclination away from vertical direction, which can be attributed to the ITO and PET film substrates possessing relatively flatter surface.
In this work, we have successfully developed an optimal process to grow highly aligned ZnO nanorod arrays on various substrates coated ZnO seed layer via aqueous solution route. Based on the coupled piezoelectric-semiconducting properties of ZnO, we have fabricated a novel mechanically powered current-generating nanodevice assembled with a ZnO nanorod arrays/PEDOT-co-PANI copolymer composite material and an Au coated PU film as a top electrode. With applying rolling force on the top electrode, the nanodevice with size 2cm×2cm was demonstrated to generate an output current density of about 1nA/cm2. The result presents that IPMC shows a possibility and a usability of the mechanically powered charge-generating nanodevices.

並列關鍵字

ZnO nanorod ； PEDOT-co-PANI copolymer ； nanocomposite materials ； wet chemical method ； RF magnetron sputtering system ； nanodevices

參考文獻

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