低成本與高效率的光觸媒對光催化產氫的開發在工業的應用性是相當重要的。本研究設計了不包含貴重金屬的WS2-MoS2奈米複合材料作為光觸媒，MoS2與WS2常被作為助催化劑幫助其他催化劑進行反應，但這兩個材料的結合具有優勢，因為相同的晶體結構且晶格常數相近，意味著兩個材料之間晶格不匹配的程度很低，使界面缺陷少。此外，因為恰當的能帶分布，使得此兩半導體異質材料能帶結構為Type-II型態，因而可以有效的分離光致電子電洞對，進而提升產氫效能。
但由於量子效應，少層數的WS2-MoS2異質結構才能有效催化，為了得到少層數WS2-MoS2異質結構，將異質結構塊材置於乙醇水溶液中以液相剝離法(Liquid Phase Exfoliation, LPE)處理後便可得到。後續光催化產氫成果顯示，未經LPE處理之2 % MoS2塊材異質結構效率為7.5 μmol·h-1·g-1，而經LPE處理之異質結構效率則達92.3 mmol·h-1·g-1，相距極大。此外亦發現若少層數WS2-MoS2異質結構含有2 %重量組成的MoS2，其催化能力最佳，分別為純材料WS2和MoS2的2.34倍和7.64倍，顯示異質結構中有較多的光致載子參與反應，達到良好的催化效果。
本研究中以少層數WS2-MoS2異質結構為催化材料，沒有使用貴重金屬可大幅降低產氫光觸媒的成本，提供二維光觸媒材料一個新的製備與應用型式。

For industrial developments, the exploitation of materials for a low-cost and efficient photocatalytic hydrogen evolution is very crucial. Herein, we implemented the study to discuss the photocatalytic hydrogen evolution of the noble-metal-free WS2-MoS2 heterostructures. The MoS2 and WS2 are often used as co-catalysts with other materials. However, it is advantageous to combine these two together. MoS2 and WS2 are with the same crystal structure and have similar lattice parameters, which implies the small lattice mismatch between MoS2 and WS2. Moreover, due to the appropriate bandgap alignments between MoS2 and WS2, the charge separation under light illumination is remarkable, which enhances the hydrogen evolution performances.
Because of the quantum effect, only the few-layered WS2-MoS2 heterostructures can catalyze effectively. To obtain the few-layered heterostructures for photocatalytic hydrogen evolution, we put bulk heterostructures in the ethanol aqueous solution for the liquid phase exfoliation, LPE. The photocatalytic H2 production analysis showed that the efficiency of untreated bulk heterostructures with 2 % of MoS2 is 7.5 μmol·h-1·g-1 and the efficiency of LPE treated heterostructures is 92.3 mmol·h-1·g-1. In addition, we found that the few-layered WS2-MoS2 heterostructures with 2 w.t.%MoS2 has the best efficiency which is 2.34, 7.64 times of pure WS2 and MoS2 respectively. It shows that more photoinduced carriers join the reaction in heterostructures and it enhances the catalytic efficiency.
In the study, we utilize ethanol aqueous solution chosen by Hansen Solubility Parameters theory to obtain the few-layered WS2-MoS2 heterostructures and which suspension solution can directly apply in photocatalytic H2 production and show the high efficiency. It is a new way to design 2D photocatalytic materials for efficient H2 production.

摘要 　-----------　　　I
Abstract----------- II
致謝 　-----------　　　III
目錄 　-----------　　　IV
圖目錄 　-----------　　　VI
表目錄 　-----------　　　VIII
第一章 緒論與文獻回顧 　-----------　　　1
1-1氫能源(Hydrogen Energy)----------- 1
1-2光催化(Photocatalysis) -----------3
1-2-1本多 – 藤嶋效應（Honda – Fujishima effect）----------- 4
1-2-2光催化分解水原理 -----------5
1-2-3犧牲劑(Scavengers)工作原理----------- 6
1-3助催化劑於光催化產氫之發展 -----------7
1-3-1電子電洞對分離(Electron-Hole Pairs Separation)原理-----------8
1-4二維材料(Two Dimensional Materials)----------- 9
1-4-1 MoS2和WS2基本性質 -----------11
1-4-2二維塊材之剝離法與檢測 -----------13
1-4-2-1機械剝離法(Mechanical Exfoliation)----------- 13
1-4-2-2鋰離子剝離法(Lithium-Assisted Exfoliation)----------- 14
1-4-2-3液相剝離法(Liquid Phase Exfoliation, LPE)----------- 15
1-4-2-4層數檢測 -----------17
1-4-3半導體異質材料能帶結構型態----------- 18
1-4-3-1 WS2-MoS2異質結構 -----------20
1-4-4 WS2-MoS2異質結構的製程與性質 -----------21
1-4-4-1化學氣相沉積 (Chemical Vapor Deposition, CVD)----------- 21
1-4-4-2水熱法（Hydrothermal Process） -----------22
1-4-4-3直接硫化法 (Sulfurization Process)----------- 23
1-4-5二維材料在光催化中的發展 -----------24
1-4-5-1提升二維材料產氫效果之方法----------- 26
1-5研究動機 -----------28
第二章 實驗步驟 -----------29
2-1水熱法製備WS2-MoS2異質結構塊材 -----------30
2-2液相剝離法製備少層數二硫化鎢-二硫化鉬異質結構 -----------31
2-3光催化產氫效能量測----------- 32
2-4儀器介紹----------- 33
2-4-1高壓釜 (Autoclave) -----------33
2-4-2液相剝離法 (Liquid Phase Exfoliation, LPE)----------- 34
2-4-3電子顯微鏡 (Scanning Electron Microscope, SEM)----------- 35
2-4-4穿透式電子顯微鏡 (Transmission Electron Microscope, TEM)----------- 36
2-4-5能量色散X-射線光譜儀 (Energy-Dispersive X-Ray Spectroscopy, EDS)----------- 37
2-4-6原子力顯微鏡 (Atomic Force Microscope, AFM) -----------38
2-4-7 X射線繞射分析儀 (X-ray Diffractometer, XRD)-----------39
2-4-8顯微拉曼光譜儀 (Micro-Raman Spectrometer)----------- 40
2-4-9吸收光譜儀 (Ultraviolet-Visible Spectroscopy, UV-VIS)------ 41
2-4-10氣相層析儀 (Gas Chromatography, GC) -----------42
第三章 結果與討論 -----------43
3-1 WS2-MoS2異質結構塊材分析 -----------43
3-1-1掃描式電子顯微鏡(SEM)分析 -----------43
3-1-2穿透式電子顯微鏡(TEM)分析----------- 45
3-1-3能量色散X-射線光譜儀(EDS)分析----------- 47
3-1-4原子力顯微鏡(AFM)分析 -----------48
3-1-5 X射線繞射分析(XRD) -----------50
3-2少層數WS2-MoS2異質結構分析----------- 51
3-2-1原子力顯微鏡(AFM)分析 -----------51
3-2-2拉曼光譜(Raman)分析----------- 53
3-2-3吸收光譜分析 -----------54
3-3光催化產氫效率分析----------- 55
3-3-1液相剝離法於光催化產氫效率之效應----------- 55
3-3-2少層數WS2-MoS2異質結構組成於光催化產氫效率之影響----------- 57
3-3-3與文獻之探討----------- 59
第四章 結論 -----------61
第五章 未來展望 -----------62
參考文獻 -----------63

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