Fabrication of metallic nanoparticles and study on its optical properties

View Statistics Email Alert RSS Feed

Information

Details

Project title

Code/計畫編號

NSC100-2112-M019-003-MY3

Translated Name/計畫中文名

金屬奈米顆粒的製作與其光學性質之研究

Project Coordinator/計畫主持人

Hai-Pang Chiang

Funding Organization/主管機關

National Science and Technology Council

Department/Unit

Department of Optoelectronics and Materials Technology

Website

https://www.grb.gov.tw/search/planDetail?id=2867804

Year

2013

Start date/計畫起

01-08-2013

Expected Completion/計畫迄

31-07-2014

Bugetid/研究經費

914千元

ResearchField/研究領域

物理
光電工程

在近幾年來電漿子的金屬奈米球殼領域是一非常有趣的主題，因為金屬奈米球殼可以增強局域的電場強度以及使用不同大小的殼-心尺寸可以改變奈米金屬球殼之吸收波長。金屬奈米球殼在過去的研究中都集中於基本的光學性質，並且也有許多的應用，例如:光熱癌症治療，利用金屬奈米球殼之表面增強拉曼散射，利用化學制備的方法將金屬奈米球殼的內徑改變為介電質或是空心，藉以改變其吸收波長，以及利用金屬奈米球殼增強表面電漿共振的靈敏度等。複合材料的光學性質研究已經持續了幾十年，例如:金屬陶瓷複合材料，一個世紀前學者J. C. Maxwell-Garnett et.al.首次發表一套很實用的理論模型稱為等效介質理論 (effective medium theory, EMT)，大多數的複合材料是將金屬混合到介電材料中，多年來許多研究應用了Maxwell-Garnett EMT，例如:高濃度的金屬顆粒、粒子的非球面幾合等等，雙金屬奈米顆粒的光學特性因其催化性質、電性與光學性質具有相當大的應用潛力而受到矚目。金與銀因它們的晶格常數幾乎一致，以及其強大的吸收等特性，常被廣泛的用於製造雙金屬奈米粒子。基於過去幾年在表面電漿共振及奈米金屬顆粒的理論與實驗上的研究經驗與成果，我們計畫利用雷射剝離法(Laser ablation)以及化學合成方法來製作奈米金屬顆粒與奈米金屬球殼，藉由生成系統中的雷射轟擊鈀材時間和聚焦透鏡與鈀材的距離可準確的控制奈米金屬顆粒的形狀及大小，以進行侷域表面電漿共振、奈米金屬顆粒的光學性質以及增進表面拉曼散射光譜方面的研究，並且將生成之奈米金屬顆粒與奈米金屬球殼混入PDMS 中形成複合材料，更進一步研究其Goos-Hanchen shifts 量測、增強螢光強度、奈米金屬顆粒複合材料的光學性質以及增進表面電漿共振生物感測器的靈敏度之研究。本計畫的第一年將著重於建立奈米金屬顆粒的理論模型、雷射剝離系統以及利用化學合成的方式製作奈米金屬顆粒以及奈米金屬球殼，理論方面建立Mie 理論模型、奈米金屬球殼與奈米金屬顆粒定域與非定域下光學性質之理論模型以及拉曼散射率、吸收和散射之理論模型，以便從理論與實驗有系統的研究奈米金屬顆粒光學現象，實驗方面我們將建立雷射剝離系統以及化學合成方法並研究製成不同奈米金屬結構。計畫的第二年將利用第一年計畫中所生成之奈米金屬顆粒加入PDMS 中使其形成奈米金屬複合材料，理論方面我們利用Maxwell-Garnet (MG)理論建立奈米金屬複合材料之理論模型並且探討複合材料中奈米金屬顆粒之群聚現象。實驗方面我們將控制不同奈米金屬顆粒結構如金-銀核殼結構或是銀-金核殼結構等等，將這些生成之結構混入PDMS 中再利用 UV-visible 量測其光學性質，並進行奈米金屬複合材料Goos-Hanchen shift 之研究。計畫的第三年則將結合奈米金屬顆粒製作技術與以及螢光時間解析系統，研究奈米金屬顆粒如何增進表面電漿共振生物感測器的靈敏度。相信此計畫三年後的研究成果，將可以對於這些奈米金屬顆粒與奈米金屬球殼相關光學特性有通盤的了解，並對於複合材料的製作、表面增強拉曼光譜、近場光學顯微術、化學或生物感測器等領域帶來新的契機。Recently, surface plasmon resonance effect of metallic nanoshells has become a very interesting research topic due to the fact that the electric field can be enhanced by surface plasmon resonance excitation of metallic nanoshells and the absorption wavelength of metallic nanoshells can be varied by different composition of core-shell. In the past years, the metallic nanoshells had many applications such as photothermal cancer therapy, surface enhanced Raman scattering (SERS), and enhanced sensitivity of biosensors. The theoretical studies of optical properties of composite materials such as cermets have been continuing for many decades, since the first publication of a very useful effective medium theory (EMT) one century ago. Most of these materials are fabricated with metallic nanoparticles embedded in a dielectric host. Alternatives and generalizations to the Maxwell-Garnett EMT have been proposed and studied by many researchers in the literature; topics include, for example, cases of high concentration of the metallic particles, particles of nonspherical geometry. In recent years, optical, electrical, and catalytic properties of bimetallic nanoparticles, such as gold core-silver sell (bimetallic nanoshells), have attracted more attentions due to fact that the lattice constants of silver and gold are alomost equal and their strong absorption in the visible wavelength. Based on our experimental and theoretical accomplishments at the research topic of surface plasmon resonance and metallic nanoparticles in the past few years, we propose to fabricate metallic nanoparticles and nanoshells by using laser ablation system or chemical synthesis such as sol-gel method and change the shape and size of metallic nanoshells by controlling the parameters of laser ablation process. After laser ablation process, we will fabricate metallic nanocomposites by mixing metallic nanoshells with PDMS solution. In this project, we will study the optical properties of metallic nanoparticles (nanoshells), Goos-Hanchen shifts of metallic nanocomposites structures and enhanced sensitivity of surface plasmon resonance (SPR) biosensor by using metallic nanoparticles. In the first year of this project, we will focus on construction of laser ablation system for nanoparticle fabrication. We will fabricate nanoshells of different composition by laser ablation system or chemical synthesis and compare the optical properties of nanoparticles with theoretical calculation. In the second year of this project, we will fabricate nanocomposites by mixing nanoshells with PDMS solution. In the theoretical study, we will establish theoretical model of nanocomposites by using Maxwell-Garnet (MG) formula and study the particle-clustering effects on the optical response of composite materials with metallic nanoparticles. In the experimental study, we will fabricate nanocomposites materials of silver (gold) core-gold (silver) shell by using laser ablation system and mixing them with PDMS solution. We then measure the optical properties of nanocomposites materials by using UV-visible spectroscopy and study Goos-Hanchen shifts of the laser light reflected from these materials. In the third year of this project, we will study enhanced sensitivity of SPR biosensor by using metallic nanoparticles. We will also employ time-resolved fluorescence technique and surface enhanced Raman scattering to study the fundamental properties of these nanopaticles fabricated by our methods. We believe the research results of this three-year project will bring a whole-through understanding of the optical properties of metallic nanoshells and metallic nanocomposites structures.

Keyword(s)

表面增強拉曼散射
奈米球微影術
抗組織胺
組織胺
surface enhaced Raman scattering (SERS)
nanosphere lithography (NSL)
Silver film over nanosphere (AgFON)
Histamine

DSpace CRIS

Fabrication of metallic nanoparticles and study on its optical properties

Details

Description