本研究利用水熱法合成二硒化鉬奈米粒子。二硒化鉬屬於過度金屬硫族化物，具有Se-Mo-Se為單位堆疊之層狀結構，屬於由掃描式電子顯微鏡影像可知二硒化鉬奈米粒子具有均勻粒子尺寸，其粒子直徑小於1微米；經由X光繞射、高解析穿透式電子顯微鏡影像及拉曼光譜儀分析，確認為具有可靠純度以及良好結晶性之二硒化鉬(2H-MoSe2, 六方晶結構)，並且用有豐富的單層至少數層結構。穿透式電子顯微鏡影像顯示水熱法合成之二硒化鉬奈米粒子晶體結構中層與層間距為0.67nm，與X光繞射圖譜之分析結果互相符合。透過X光光電子能譜儀以及能量散步分析儀之分析確認水熱法合成二硒化鉬奈米粒子具有均勻之組成，且不存在氧化鉬之雜質。高角度環狀暗場影像中亦沒有顯著介面結構。
進一步利用壓電響應力顯微鏡以及穿隧原子力顯微鏡分析分別證實水熱法合成二硒化鉬之正、逆壓電特性。基於此一材料特性，對二硒化鉬奈米粒子進行壓電觸媒實驗分析，結果顯示10mg二硒化鉬奈米粒子在超音波震盪作為外加應力源之狀況下能在120秒將50ml 10ppm羅丹明染料水溶液降解至完全透明。

We demonstrate a hydrothermal process to synthesize single to few layers MoSe2 nanoflowers which exhibit a reliable purity and cristallinity. The crystal structure of the MoSe2 nanoflowers has been confirmed by X-ray diffraction pattern, Raman, and High-resolution transmission electron microscopy (HRTEM). On the basis of the scanning electron microscope (SEM) image, the size of the MoSe2 nanoflowers obsess diameter less than 1μm. HRTEM image reveals that the MoSe2 nanoflowers possess a great number of the single- and few-layers, which further confirms that our nanoflowers display the plentiful amount of active surface sites. In addition, the lattice fringes between each single layer is about 0.67 nm, which is slightly larger than the reported value of 0.62 nm for the MoSe2. The piezoresponse force microscopy and tunneling atomic force microscopy analysis further support that the MoSe2 nanoflowers exhibits significantly piezoelectric potential which is generated from the active surface sites of the petals in the MoSe2 nanoflowers. Through the piezocatalyst experiment we reveal that these MoSe2 nanoflowers can successful turn dye solution in 120 second with assist of ultrasonic vibration as a mechanical force to induce piezocatalytic activity.

第一章 緒論 1
1.1 前言 1
1.2 研究動機 3
第二章 文獻回顧 4
2.1 光觸媒(Photocatalyst) 4
2.1.1 傳統光觸媒材料 6
2.1.2 修飾光觸媒提升其效能 10
2.2 壓電效應應用於光觸媒系統(Photocatalyst system) 14
2.2.1 壓電效應（piezoelectric effect） 14
2.2.2 壓電勢(Piezo-potential)促進氧化鋅光觸媒對有機染料之降解效果 14
2.3 壓電觸媒 17
2.3.1 二維過渡金屬硫族化物材料具有壓電效應 17
2.3.2 壓電觸媒 21
2.3.3 二硫化鉬奈米花作為壓電觸媒之表現 23
2.4 二硒化鉬 27
2.5 二硒化鉬合成方式 29
2.5.1 化學氣相沉積法(chemical vapor deposition；CVD) 29
2.5.2 水熱法(hydrothermal method) 31
2.6 二硒化鉬於觸媒領域之應用 34
2.6.1 光觸媒 34
2.6.2 染料敏化電池(Dye-sensitized solar cell) 37
2.6.3 產氫 40
第三章 實驗方法與步驟 42
3.1 前驅物製備 43
3.2 水熱法製程 44
3.3 材料特性分析 45
3.3.1 場發射掃描式電子顯微鏡 45
3.3.2 WAG廣角X光繞射儀 46
3.3.3 拉曼光譜儀 47
3.3.4 高解析穿透式電子顯微鏡暨能量散佈分析儀器 48
3.3.5 X光光電子能能譜儀 49
3.3.6 壓電響應力顯微鏡 50
3.3.7 穿隧原子力顯微鏡 51
3.3.8 壓電觸媒 52
第四章 結果與討論 54
4.1 掃描式電子顯微鏡表面形貌分析 54
4.2 X光繞射之結構與成分分析 57
4.3 高解析穿透式電子顯微鏡暨能量散佈分析儀器之晶體結構分析 59
4.4 拉曼光譜分析 62
4.5 X光光電子能譜分析 64
4.6 壓電性質分析 66
4.7 壓電觸媒催化實驗與分析 69
4.7.1 壓電催化染料降解 69
4.7.2 壓電催化染料分解機制 71
第五章 結論 73
第六章 未來展望 74
第七章 參考文獻 75

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