臺灣博碩士論文加值系統

本實驗以石墨烯為導電基板，在其上成長奈米碳管束陣列，並利用此奈米碳管束陣列為模板披覆二氧化釕及二氧化銥做為電化學電容器之電極材料。奈米碳管具有高導電性、高化學穩定性及高比表面積之特性，並可經由光微影技術定義其圖形之樣式以增加與電解液之接觸面積。而二氧化釕及二氧化銥擁有良好的偽電容特性，因此本實驗所利用之二氧化釕及二氧化銥披覆於奈米碳管/石墨烯上之結構可有效地提高電雙層電容特性。由實驗結果得知，當所設計之奈米碳管束陣列圖形之孔洞直徑為10 微米且其間距為5 微米時，具有最佳之電化學電容特性。其中以定電流量測法測得之奈米碳管束陣列之比電容值為6.9 F/g，二氧化釕披覆於奈米碳管束陣列上之比電容值為121.1 F/g，二氧化銥披覆於奈米碳管束陣列上之最佳比電容值為129.4 F/g。在電容穩定性之量測方面，經過1000次之充放電後，二氧化釕及二氧化銥披覆於奈米碳管束陣列上之電容特性皆可保持穩定。本實驗所製作之二氧化釕及二氧化銥披覆於奈米碳管束陣列結構皆為良好之電化學電極材料。

Graphene was used as a conductive substrate in this study. Vertically aligned carbon nanotube (CNT) arrays were grown onto the graphene, which was used as a template for RuO2 and IrO2 nanostructure growth. The nanostructures were then used as a material for building an electrochemical capacitor. CNTs have many special properties such as high aspect ratio, good conductivity and chemical stability. By synthesizing CNTs with the aid of photolithography techniques, the CNT pattern can be designed to maximize the electrolyte contact area. RuO2 and IrO2 exhibit good pseudo-capacitor characteristics, and therefore a CNTs/graphene coated with RuO2 and IrO2 nanostructures could be used to effectively enhance the electrochemical capacitor characteristics. From the experimental results the optimal design pattern was 10 micrometer pore diameter with a separation of 5 micrometer between pores. The specific capacitances of CNTs/graphene, RuO2/CNTs/graphene and IrO2/CNTs/graphene were 6.9, 121.1, and 129.4 F/g, respectively. Long-term testing was conducted by carrying out 1000 charge-discharge cycles with subsequent measurements carried out. The CNTs/graphene, RuO2/CNTs/graphene and IrO2/CNTs/graphene could maintain stable electrochemical characteristics. The synthesized CNTs/graphene, RuO2/CNTs/graphene and IrO2/CNTs/graphene were suitable for the electrochemical applications.

Abstract (in Chinese)
Abstract (in English)
Contents
Figure captions
Table list
Chapter 1 Introduction
1.1 Carbon nanotube
1.1.1 Discovery of carbon nanotube
1.1.2 Structure of carbon nanotube
1.1.3 Property of carbon nanotube
1.2 Graphene
1.2.1 Discovery of graphene
1.2.2 Structure of graphene
1.2.2.1 Structure of single-layer graphene
1.2.2.2 Structure of bilayer and multilayer graphene
1.2.3 Electron energy band of graphene
1.2.4 Phonon dispersion of graphene
1.2.5 Raman spectroscopy of graphene
1.2.6 Formation methods of graphene
1.3 Electrochemical double layer capacitor
1.3.1 Historical background
1.3.2 Introduction to electrochemical double layer capacitor
1.3.3 Introduction to pseudo-capacitor
1.4 Motivation
Chapter 2 Experimental
2.1 Experimental procedure
2.2 Process
2.2.1 Preparation of substrate
2.2.2 Formation of graphene
2.2.3 Transfer of graphene
2.2.4 Photolithography
2.2.5 Electron beam evaporator
2.2.6 Growth of Carbon Nanotube
2.2.7 Coverage of RuO2
2.2.8 Coverage of IrO2
2.3 Analysis and measurement
2.3.1 Scanning electron microscopy and energy dispersive X-ray spectroscope
2.3.2 Transmission electron microscope
2.3.3 Raman spectroscopy
2.3.4 Electrochemical Analyzer
2.3.4.1 Cyclic voltammetry
2.3.4.2 Charge-discharge measurement
2.3.4.3 Electrochemical impedance spectroscopy
Chapter 3 Results and discussion
3.1 Electrode material analysis
3.1.1 Definition of the pattern for CNT growth
3.1.2 Morphological characterization
3.1.3 Internal morphological characterization
3.1.4 Analysis of Raman spectrum
3.2 Electrochemical characteristics of EDLC
3.2.1 Cyclic voltammetry and charge-discharge measurement for CNT
3.2.2 Cyclic voltammetry for pseudocapacitor
3.2.3 Charge-discharge measurement
Chapter 4 Conclusions
Reference
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