劉沂欣Liu, Yi-Hsin謝宗恩Hsieh, Tzung-En2019-09-042023-08-162019-09-042018http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22G060542016S%22.&%22.id.&http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/100178本研究專注於研究強量子侷限效應的硒化鎘奈米材料，並分別從零維的魔術尺寸奈米團簇物與二維單層結構之奈米片進行探討。於魔術尺寸奈米團簇物之研究當中，我們以目前文獻報導尺寸最小也最穩定的(CdSe)13奈米團簇物作為研究對象，嘗試解析其結構。在本論文中，我們應用多種非破壞性的鑑定方法，如紫外光-可見光吸收光譜、X光繞射技術、X光小角/廣角散射技術、X光光電子能譜、X光吸收光譜與固態核磁共振技術，研究(CdSe)13¬團簇物之電子結構、合成機制、原子結構排列、團簇物尺寸、原子配位環境與原子化學環境等，以建構雙生團簇物模型並驗證之。除了實驗部分以外，本研究更與理論計算實驗室合作，以DFT計算方法建構團簇物之結構模型，並模擬其電荷密度與相對能量，進一步與實驗部分數據互相驗證並證實雙生團簇物之存在合理性。 在二維奈米材料研究中，我們選擇相同的CdSe半導體材料作為主體，以雙頭胺配位基合成高結晶性之二維單層CdSe奈米片，並以奈米片作為主要材料，進行陰/陽離子置換研究。本論文選用同為第十六族之S作為陰離子置換元素，嘗試探討S取代反應於二維奈米片中的位向選擇性以及其對奈米片的光學，電學性質之影響。硫化反應後的具孔洞性質的CdSe/CdS奈米片更進一步應用於氮氣與二氧化碳吸附研究。陽離子置換的研究當中，我們選擇具高電荷傳導性的Fe,Ni以及具有特殊光學性質的Ag作為陽離子交換試劑，嘗試調整奈米片之光學性質，並進一步發展光電或熱電材料。In this research, we focus on structure resolution and applications of strong quantum confined-cadmium selenide semiconductor with 0D (nanocluster) and 2D (nanosheets) morphologies. In nanocluster part, we resolved the structure of smallest-magic-sized (CdSe)13 nanoclusters. With a combination of nondestructive SAXS, WAXS, XRD, XPS, EXAFS, and MAS NMR techniques, we are able to verify the phase transformation, shape, size dimension, local bonding, and chemical environments of (CdSe)13 nanoclusters, which are indicative of a twin-cluster model. Additionally, the size, shape, bond lengths, dipole moment, and charge densities of the proposed “twin-tubular geometry” calculated by computational methods match consistently with our experimental results. For 2D nanosheets, we reported the post synthetic researches of elements doped CdxM1-xSe(en)0.5 and CdSeyX1-y(en)0.5 nanosheets from strong quantum confined CdSe(en)0.5 nanosheets via ion exchange reaction with the via various cationic/anionic reagents. The active site of sulfurization reaction is determined and the “porous nanosheets” is synthesized while sulfurization. In addition, Fe, Ni, Ag were employed as cationic reagent since the unique optical properties and outstanding charge transfer ability which have been reported. We try to develop a new class of 2D nanomaterial applied in photovoltaic and photocatalytic fields.硒化鎘魔術尺寸團簇物小角散射X光吸收光譜自組裝二維結構陰陽離子交換光催化水分解Cadmium selenidemagic-size clustersSAXSXASself-assembly2D structureanion/cation exchangephotocatalytic water splitting