在本論文中，根據第一原理，採用CASTEP 程式碼計算並討論不同混掺系統的介面性質，尤其關注混掺系統的電荷轉移行為與能帶排列。在此，我們選定聚噻吩/奈米碳管、聚噻吩/石墨烯與金/石墨烯做為我們研究的對象。電子結構有經過幾何結構最佳化調整，並列出不同系統的束縛能與分子間距資訊。根據計算結果，我們提出了一些影響混掺系統電荷轉移行為與能帶排列的重要因素，提供實驗上設計元件的參考。對於金屬/半導體的混掺系統，我們有列出其蕭特基能障之值。

In this thesis, we employed the first-principle calculations to investigate the interface properties of several hybrid systems using CASTEP code. We focus on the charge transfer behavior and the band alignment of each system. The hybrid systems we used including polythiophene/carbon nanotube, polythiophene/graphene and gold/graphene systems. The electronic structures, such as the binding energy and the intermolecular distance, were investigated and full-optimized. We suggest some factors may influence the charge transfer behavior and the band alignment of different hybrid systems. According to these details, we give some advices on designing devices. The Schottky barrier heights of different metal/semiconductor hybrid systems were also calculated.

口試委員會審定書
致謝 i
摘要 iii
Abstract iv
Table of Contents v
Figures viii
Tables xi
Chapter 1 Introduction 1
Chapter 2 Theory 9
2.1 Origin 9
2.2 Overview of Density Functional Theory 9
2.3 Thomas-Fermi Model 11
2.4 Hohenberg-Kohn Theorem 11
2.5 Born-Oppenheimer Approximation 13
2.6 Kohn–Sham Equations 13
2.7 Local Density Approximation (LDA) and Generalized Gradient Approximation (GGA) 15
2.8 Self-Consistent Calculations 16
2.9 Cambridge Serial Total Energy Package (CASTEP) 17
2.10 Band Structure 18
2.11 Density of States (DOS) 19
2.12 Electron Density Difference 21
Chapter 3 Modeling and Calculation Method 25
3.1 Polythiophene and CNT 25
3.2 Maximum-Binding-Energy Method 28
3.3 Calculation Details 29
Chapter 4 P3ET/CNT Hybrid System 30
4.1 P3ET/Pristine CNT System 30
4.1.1 Modeling 30
4.1.2 Results and Discussions 31
4.1.3 Summary 33
4.2 P3ET/Surface-Modified CNT System 34
4.2.1 Modeling 34
4.2.2 Results and Discussions 35
4.2.3 Summary 44
4.3 P3ET/Acyl Chloride-Modified CNT System 45
4.3.1 Modeling 45
4.3.2 Results and Discussions 46
4.3.3 Summary 49
4.4 C60/ P3ET/Surface-Modified CNT System 50
4.4.1 Modeling 50
4.4.2 Results and Discussions 51
4.4.3 Summary 59
Chapter 5 P3ET/Graphene System 60
5.1 P3ET/Surfaced-Modified Graphene System 60
5.1.1 Modeling 60
5.1.2 Results and Discussions 62
5.1.3 Summary 64
5.2 P3ET/Doped Graphene System 65
5.2.1 Modeling 65
5.2.2 Results and Discussions 67
5.2.3 Summary 75
Chapter 6 Gold/Graphene System 77
6.1 Gold/Doped Graphene System 77
6.1.1 Modeling 77
6.1.2 Results and Discussions 79
6.1.3 Schottky Barrier Height 80
6.1.4 Summary 86
6.2 Gold/Graphane and Gold/Graphene Oxide System 88
6.2.1 Modeling 88
6.2.2 Results and Discussions 90
6.2.3 Schottky Barrier Height 92
6.2.4 Summary 97
Chapter 7 Conclusions 98
Reference 102

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