請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/72581
標題: | 接合到合成金屬奈米顆粒的量子點之發光行為 Emission Behaviors of Quantum Dots Linked onto Synthesized Metal Nanoparticles |
作者: | Cheng-Jin Cai 蔡誠晉 |
指導教授: | 楊志忠 |
關鍵字: | 表面電漿子, Surface Plasmon, |
出版年 : | 2019 |
學位: | 碩士 |
摘要: | 我們合成八種不同表面電漿子共振波長的金屬奈米顆粒,包含兩種純金奈米顆粒、兩種純銀奈米顆粒和四種銀/金之核/殼奈米顆粒。我們將每種金屬奈米顆粒接上PEG之後再接上紅光量子點,觀察量子點的發光特性。我們利用掃描式電子顯微鏡的影像顯示量子點接上不同金屬奈米顆粒的形貌,以時間解析光致發螢光和內部量子效率的量測用來瞭解量子點的放光效率。光致發螢光衰減時間和內部量子效率一致顯示表面殘留citrate的純銀奈米顆粒相較於表面殘留CTAC的純金奈米顆粒,其光致發螢光衰減時間較短,內部量子效率較高。這些結果歸因於PEG置換citrate效率相較於置換CTAC較高。而在銀/金之核/殼奈米顆粒樣品之中,金含量越高的樣品造成越長的光致發螢光衰減時間和越低的內部量子效率。基於此結果,我們可以優化金屬奈米顆粒的結構,透過表面電漿子共振增強量子點的吸收再發光效率,最大化藍光源轉成紅光的光色轉換效率。 Eight different metal nanoparticle (NP) samples in total of different localized surface plasmon (LSP) resonance wavelengths, including two pure Au NP samples, two pure Ag NP samples of quite different sizes, and four Ag/Au core/shell NP samples of different compositions are synthesized. After linking with PEGs of different molecular weights, those NP samples are linked with quantum dots (QDs) for observing the emission behaviors of the QDs. Scanning electron microscopy images show the linkage of QDs onto metal NPs of different samples. Time-resolved photoluminescence (PL) and internal quantum efficiency (IQE) measurements are undertaken for understanding the QD emission efficiencies. The consistent PL decay time and IQE show that the pure Ag NP samples with residual surface citrate have shorter PL decay times and higher IQEs, when compared with the NP samples of pure Au. Also, between the two pure Au NP samples, the one with residual surface citrate has a shorter PL decay time and a higher IQE, when compared with the other pure Au NP sample with residual surface CTAC. These results are generally attributed to the higher efficiency of replacing citrate by PEG, when compared to CTAC. Among those Ag/Au core/shell NP samples, generally a higher Au content leads to a longer PL decay time and a lower IQE. Based on these results, we can optimize the metal NP condition for maximizing the color conversion efficiency from a blue-light source into red light through the LSP-resonance enhanced QD absorption-reemission process. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/72581 |
DOI: | 10.6342/NTU201902281 |
全文授權: | 有償授權 |
顯示於系所單位: | 光電工程學研究所 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-108-1.pdf 目前未授權公開取用 | 2.46 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。