(一)二氧化鈦奈米管陣列之合成及分析 (二)聚苯胺奈米管之合成及在氣體感測器上的應用

(一) Fabrication of TiO2 nanotube arrays (二) Fabrication of polyaniline nanotubes and application on the gas sensor

黃詩閔(Shin-min Huang)

指導教授 ： 楊思明

國立中央大學/工學院/化學工程與材料工程學系/碩士(2007年)

摘要

本研究的第一部分為二氧化鈦奈米管陣列之合成及分析；採用簡單的二極式電化學陽極氧化法，以定電壓20V在含氟的有機甘油電解液中陽極氧化高純度的金屬鈦片，在鈦片上製備出高規則且高長寬比的二氧化鈦奈米管陣列。並藉由SEM、TEM影像分析二氧化鈦奈米管陣列表面及內部形態，由EDX分析進行二氧化鈦的成分鑑定，再由選區電子繞射(SAED)來判別二氧化鈦奈米管煅燒後的晶型結構；最後透過UV光譜及XRD鑑定所形成的產物為二氧化鈦anatase相的晶型結構。
此外，第二部分為聚苯胺奈米管之合成及在氣體感測器上的應用；本實驗首先採用兩步陽極氧化的方式經由電解液、電壓及溫度等參數控制，可成功製成50nm、30nm及20nm三種孔徑大小的高規則氧化鋁膜模板，接著使用電化學的方式在自製不同孔徑的模板內合成聚苯胺奈米管/線；並藉由SEM及TEM影像分析聚苯胺奈米管/線的表面及內部形態，以FT-IR、CV對合成的產物進行定性分析，證實在自製氧化鋁膜內所合成出的確實為聚苯胺結構。另一方面，以導電高分子聚苯胺為感測氣體材料將聚苯胺製備成傳統薄膜、奈米纖維及奈米管三種不同的形態結構，分別對NO2及NH3兩種氣體進行測試。由實驗結果比較其靈敏度發現，對NO2及NH3兩種氣體之靈敏度皆為：奈米管＞奈米纖維＞傳統薄膜，並且NO2氣體比NH3氣體的反應靈敏度高出許多。

關鍵字

二氧化鈦 ； 陽極氧化 ； 氣體感測器 ； 聚苯胺

並列摘要

In this thesis, we study two research topics: firstly, we report the preparation of TiO2 nanotubes by potentiostactic anodizing process. Titanium foil was anodizing at a voltage of 20 V in a glycerol solution containing NH4F to fabricate highly ordered and high aspect ratio (L/D) TiO2 nanotubes. SEM and TEM photographs, show the morphology and hollow tubular structure of TiO2 nanotube arrays. Additionally, the products was characterized by EDX, SAED, UV and XRD to demonstrate that TiO2-anatase structure is formed upon thermal annealing after anodization.
Secondly, We successfully synthesize polyaniline nanotubes by electrochemical method in self-organized anodic aluminum membrane (AAO), moreover, we study the properties of conducting polyaniline tube as gas sensor. Highly ordered anodic aluminum membranes with uniform pore diameters of 50 nm, 30 nm and 20 nm have been fabricated successfully by two-step anodizing process. We synthesized polyaniline nanotubes(wires) within the holes of the membrane. SEM and TEM were used to observe the surface and inner structure of the polyaniline nanotubes(wires). FT-IR spectra and CV show that the products synthesized in the pores of AAO membranes are polyaniline. The conducting form of polyaniline(PANI) have been tested as gas sensing material. The investigations were performed with three different structures of polyaniline films for detecting gaseous NH3 and NO2. The results showed that the sensitivity of both NO2 and NH3 gas follow the order: PANI nanotubes＞PANI fibers＞conventional PANI film. The sensitivity for NO2 are superior them the sensitivity of NH3.

並列關鍵字

polyaniline ； anodization ； titanium oxide ； gas sensor

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