English  |  正體中文  |  简体中文  |  Items with full text/Total items : 73032/73032 (100%)
Visitors : 23057450      Online Users : 376
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version

    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/65009

    Title: 以光譜學研究含稀土元素發光晶體內之能量轉移過程
    Authors: 蕭郁如;Hsiao,Yu-Ru
    Contributors: 化學學系
    Keywords: 以光譜學研究含稀土元素發光晶體內之能量轉移過程
    Date: 2014-07-29
    Issue Date: 2014-10-15 14:38:01 (UTC+8)
    Publisher: 國立中央大學
    Abstract: 本論文使用中溫水熱法合成不同比例稀土元素之R2(C8H10O4)3晶體(R= Y, Eu, Tb; C8H10O4= 1,4-cyclohexanedicarboxylate)和高溫固態合成法合成K4(UO2)Eu2Ge4O14。合成的化合物以單晶X光繞射鑑定晶體結構並以粉末X光繞射實驗鑑定晶體的純度,再以感應耦合電漿原子發射光譜做鑭系元素的定量。我們測量了這些晶體的光致放光光譜、激發光譜及其時間解析光譜以釐清其能量轉移機制與速率。藉由分析這些光譜資料,我們證明Eu2(C8H10O4)3 和Tb2(C8H10O4)3中之濃度淬熄現象為上能階之能量轉移,而混合Eu3+及Tb3+之化合物中,Tb3+轉移能量給Eu3+之機制則為光子間的能量轉移,並且在不同波長有不同之轉移速率和機制。在K4(UO2)Eu2Ge4O14化合物中,我們證明了UO22+會將能量轉移予Eu3+放光,且發現在不同激發波長其轉移速率也有所不同。;Mid-temperature hydrothermal and high-temperature solid-state synthesis techniques have been respectively used for the synthesis of R2(C8H10O4)3, (R=Y, Eu, Tb, and C8H10O4= 1,4-cyclohexanedicarboxylate) and that of K4(UO2)Eu2Ge4O14. Single-crystal and powder X-ray diffraction (XRD) data of these compounds have been obtained for confirming their structure and purity. The compositions of lanthanide elements were verified by the inductively coupled plasma atomic emission spectroscopy (ICP-AES). We have recorded the photoluminescence (PL) spectra, excitation spectra, and time-resolved spectra for clarifying the energy transfer mechanisms and the transfer rates in these compounds. Based upon the analysis of our data, we show that the concentration quenching in Eu2(C8H10O4) as well as in Tb2(C8H10O4) is an energy migration process, while the energy transfer from Tb3+ to Eu3+ in the Eu3+/Tb3+ hybrid compounds is a photon energy transfer process and the Tb3+-Eu3+ energy transfer rate is wavelength-dependent. In addition, we have also confirmed that the Eu3+ emission in K4(UO2)Eu2Ge4O14 is activated by the sensitization of UO22+ and the energy transfer rate also highly depends on the excitation wavelength.
    Appears in Collections:[化學研究所] 博碩士論文

    Files in This Item:

    File Description SizeFormat

    All items in NCUIR are protected by copyright, with all rights reserved.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback  - 隱私權政策聲明