Novel Photofunctional Multicomponent Rare Earth (Eu^sup 3+^, Tb^sup 3+^, Sm^sup 3+^ and Dy^sup 3+^) Hybrids with Double Cross-linking Siloxane Covalently Bonding SiO^sub 2^/ZnS Nanocomposite

摘要

Zinc sulfide (ZnS) quantum dot is modified with 3-mercaptopropyltrimethoxysilane (MPTMS) to obtain MPTMS functionalized SiO^sub 2^/ZnS nanocomposite. Novel rare earth/ inorganic/organic hybrid materials are prepared by using 3(triethoxysilyl)-propyl isocyanate (TESPIC) as an organic bridge molecule that can both coordinate to rare earth ions (Eu^sup 3+^, Tb^sup 3+^, Sm^sup 3+^ and Dy^sup 3+^) and form an inorganic Si-O-Si network with SiO^sub 2^/ZnS nanocomposite after cohydrolysis and copolycondensation through a sol-gel process. These multicomponent hybrids with double cross-linking siloxane (TESPICMPTMS) covalently bonding SiO^sub 2^/ZnS and assistant ligands (Phen = 1,10-phenanthroline, Bipy = 2,2'-bipyridyl) are characterized and especially the photoluminescence properties of them are studied in detail. The luminescent spectra of the hybrids show the dominant excitation of TESPIC-MPTMS-SiO^sub 2^/ZnS unit and the unique emission of rare earth ions, suggesting that TESPIC-MPTMS-SiO^sub 2^/ZnS unit behaves as the main energy donor and effective energy transfer take place between it and rare earth ions. Besides, the luminescent performance of BipyRE-TESPIC-MPTM-SiO^sub 2^/ZnS hybrids are superior to that of Phen-RE-TESPIC-MPTMS-SiO^sub 2^/ZnS ones (RE = Eu, Tb, Sm, Dy), which reveals that Bipy or Phen only act as structural ligand within the hybrid systems. [PUBLICATION ABSTRACT]