此研究以溶液合成法合成出金屬奈米粒子與金屬/半導體的異質結構，我們利用磷酸三辛脂(TOP)以及油胺於高溫下還原氯化亞銅，再藉由熱注射法將奈米粒子的成核與成長階段分開，進而得到形狀與尺寸均一的銅奈米粒子。我們利用SEM與TEM觀察奈米粒子的表面形貌與投影影像，以X光繞射圖譜分析各結晶面的情形，再利用高解析電子能譜儀與傅立葉轉換紅外光譜儀探討產物的表面性質。而由於奈米銅是另一個於可見光區域具有表面電漿共振特性的貴重金屬，於是我們也利用UV可見光譜儀與暗場散射顯微鏡來探討其光學性質。
而在金屬與半導體異質結構的合成控制上，我們利用陽離子交換技術得到金與硒化鎘的核殼結構，除此之外，我們也藉由調整硝酸鎘加入的量來控制殼層厚度。我們利用高解析TEM，SAED及EDX分析產物的結晶結構與組成，並利用UV可見光譜儀探討產物殼層厚度與光學性質的關係。最後，我們將此異質結構應用在光催化的測試上，並探討電荷分離的機制與不同殼層厚度對光催化效率的影響。

This study aims to obtain metal nanoaprticles and metal@semiconductor core-shell heterostructures. With controllable shape and size were used to TOP and oleylamine to reduce copper chloride at high temperature, and separate the nucleation and growth process by a hot injection method to obtain the Cu nanoparticles with monodispersity in size and shape. We characterize the morphology and the projected image of nanoparticles via SEM and TEM. X-ray diffraction patterns were used to analyze the crystalline structure of products, and to study their surface properties via both XPS and FTIR measurements. Nanosized Cu is a noble metal known to display localized surface plasmon resonance (LSPR) in the visible region. Hence, we investigated their optical properties by UV-visible spectroscopy and characterize the optical properties of single particle via dark-field microscopy.
We obtained Au@CdSe core-shell nanorods by applying a catoin-exchange strategy. The shell thickness of products can be tuned by adding different amount of Cd(NO3)2. We used HRTEM, SAED and EDX analysis to verify the crystallographic geometry and composition of the products. We also discussed the relationship between shell thickness and optical property via UV-visible spectroscopy. Finally, the charge transfer phenomenon between Au and CdSe was investigated by different extinction sources, including UV light and a 532 laser.

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