異向性金屬奈米微粒之合成與性質研究

Studies on the synthesis and properties of Anisotropic shapes metal nanoparticles

邱顯安(Hsien-An Chiu)

指導教授 ： 廖建勛

元智大學/工程學院/化學工程與材料科學學系/碩士(2006年)

摘要

本研究主要利用晶核成長法(Seed-mediated growth method) ，製備具有從可見光至近紅外光不同吸收波長的金奈米桿，並藉由改變硝酸銀添加量、晶核液添加量、溫度及加熱時間調控其縱向電漿子共振吸收能帶。紫外-可見光吸收光譜儀(UV/Vis)數據顯示，最大吸收波長範圍從570nm至大於800nm，穿透式電子顯微鏡(TEM)觀測其幾何尺寸為桿狀的金奈米微粒。藉由加熱製備熱形變金奈米桿過程中，金奈米桿長度維持在47nm左右，金奈米桿直徑則隨著反應溫度升高而增大，由9nm增大至31nm，使得金奈米桿縱橫比從4.85減小至1.55。金奈米桿縱橫比的減少，造成縱向電漿子共振吸收能帶則從近紅外光區(25℃)藍移至可見光區(90℃)，金奈米桿直徑增大，造成橫向電漿子共振吸收能帶由507nm(25℃)紅移至532nm(90℃)。本篇還利用晶核成長法及光化學反應製備銀奈米桿及銀奈米三角平板，並與上述之金奈米桿綜合，探討其光學性質。

關鍵字

金奈米桿 ； 晶核成長法 ； 銀奈米桿 ； 銀奈米三角平板

並列摘要

In this study, the gold nanorod is prepared by seed-mediated growth method. The longitudinal surface plasmon resonance (SPR) absorption of gold nanorod from visible to near-IR range is tuned by the amount of silver nitrate, seed solution, reaction time and temperature during synthesis. The maximum of absorption wavelength ?釽ax ranges from 570 nm to larger than 800 nm from the results of UV-vis spectra. The TEM images show that the morphology of formed gold nanoparticles are nanorod. During the thermal-shaped process of gold nanorod, the length of nanorod remains as about 47 nm. However, the diameter of nanorod increases from 9 nm to 31 nm as increasing temperature that results in a decrease of aspect ratio of nanorod from 4.85 to 1.55. The decrease of aspect ratio of nanorod causes the blue shift of SPR absorption from near-IR to the visible range. On the other hand, the transverse SPR absorption reveals a slight red-shift from 507 nm to 532 nm due to the increase of diameter of gold nanorod. The preliminary results of optical results of silver nanorod and silver triangular nanoplate prepared by seed-mediated growth and photochemical method, respectively, are compared with the gold nanorod mentioned above.

並列關鍵字

gold nanorod ； seed-mediated growth method ； silver nanorod ； silver triangular nanoplate

參考文獻

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