近年來，由於劇烈的氣候變遷以及石化燃料漸趨匱乏，產氫的相關的研究也獲得越來越多的關注。而光催化水解就是一種十分具有潛力的產氫方式。
本研究聚焦在將具有電漿增益效益的TiN/GaP 奈米線異質結構應用在光催化水解產氫。透過氣液固相 (vapor-liquid-solid) 法來合成GaP 奈米線，為了進一步增加GaP 奈米線的產氫量，加上TiN薄膜以形成異質結構。利用電子束蒸鍍，在GaP 奈米線上分別鍍上厚度為5奈米、10奈米、15奈米以及20奈米的TiN。藉由表面電漿共振 (surface plasmon resonance) 效應來優化光催化水解的效率。實驗結果顯示，當TiN的厚度為15奈米時會表現出最佳的增益效果，比起單純的GaP奈米，氫氣產量可提升約3.15倍。

The production of hydrogen has recently gained a great deal of interest owing to drastic climate change and the scarcity of fossil fuels. One promising method for producing hydrogen is through photocatalytic water splitting.
The present research focused on the plasmonic enhancement of photocatalytic water splitting with TiN/GaP nanowires heterostructures. GaP nanowires were synthesized through a vapor-liquid-solid (VLS) growth process. To further enhance the efficiency of hydrogen production, TiN was introduced. The heterostructures were fabricated by depositing a TiN film onto GaP nanowires using electron beam evaporation. GaP nanowires were coated with TiN of thicknesses 5 nm, 10 nm, 15 nm, and 20 nm. The surface plasmon resonance (SPR) effect was found to increase the efficiency of hydrogen production. The results demonstrated that photocatalysts with a TiN thickness of 15 nm on GaP NWs exhibited the optimal enhancement effect, leading to an increase of 3.15 times in hydrogen production compared to pure GaP nanowires.

Abstract I
摘要 II
致謝 III
Contents IV
Chapter 1 Introduction 1
1.1 Research Background 1
1.1.1 Energy Crisis 1
1.1.2 Overview of Hydrogen Production 4
1.1.3 Photocatalytic Water Splitting 9
1.2 Nano Materials 14
1.2.1 Overview 14
1.2.2 Categories of Nanomaterials 16
1.2.3 Vapor-Liquid-Solid (VLS) Growth Method 17
1.3 Plasmonic Effect 19
1.3.1 Overview 19
1.3.2 Surface Plasmon Polariton (SPP) 19
1.3.3 Localized Surface Plasmon Resonance (LSPR) 21
1.3.4 Photocatalytic Plasmonic Enhancement 23
1.4 Material Selection 26
1.4.1 Gallium Phosphide 26
1.4.2 Titanium Nitride 27
1.5 Motivation 28
Chapter 2 Experimental Section 30
2.1 Experimental Equipments and Instruments 30
2.1.1 Three-Zone Furnace 30
2.1.2 Electron Beam Deposition System 31
2.1.3 Scanning Electron Microscope (SEM) 32
2.1.4 X-ray Diffractometer 34
2.1.5 Transmission Electron Microscope (TEM) 36
2.1.6 Ultraviolet-Visible Spectroscope (UV-Vis) 37
2.1.7 Raman Spectroscope 38
2.1.8 Gas Chromatography (GC) 39
2.1.9 Finite-Difference Time-Domain (FDTD) Analysis 40
2.2 Experimental Procedures 41
2.2.1 Preparation of Substrates 41
2.2.2 Synthesis of GaP Nanowires 42
2.2.3 Fabrication of TiN/GaP Nanowires Heterostructures 45
Chapter 3 Results and Discussion 46
3.1 Characteristics of GaP Nanowires 46
3.1.1 SEM Observation 46
3.1.2 XRD Analysis 47
3.1.3 EDS Measurement 49
3.1.3 TEM Observation 50
3.1.4 UV-Vis Absorbance Spectrum 52
3.1.5 Raman Spectroscopy Analysis 54
3.2 Hydrogen Production Measurement 55
3.3 Characteristics of TiN/GaP Heterostructures 60
3.3.1 UV-Vis Absorbance Spectra 60
3.3.2 Raman Spectra 61
3.3.3 FDTD Simulation 63
3.3.4 Enhancing Mechanism of TiN/GaP Heterostructures 67
Chapter 4 Summary and Conclusions 68
Chapter 5 Future Prospects 69
5.1 Application of Atom-Doping Mechanism for Modulating Hydrogen Production Activity in GaP Nanowires in Photocatalytic Water Splitting 69
5.2 Application of Composite GaP nanowires Utilizing Z-Scheme Mechanism in Photocatalytic Water Splitting 70
Appendix 72
References 73

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