Highly transparent and luminescent lanthanide ion-containing bridged polysilsesquioxanes

Novel luminescent bridged polysilsesquioxane monoliths of high transparency have been obtained by hydrolysis and condensation of the precursor under acidic conditions. The monoliths were characterized by FTIR spectroscopy, photoluminescence spectroscopy, and SEM, and they have been used as hosts of Eu(3+), Tb(3+) and Nd(3+) ions. The luminescence lifetime of Tb(3+) in this host was 2.1 ms. The interaction between the host and the lanthanide ions could be confirmed by FTIR spectra. The number of water molecules coordinated to the Eu(3+) ions was determined to be one. Incorporation of Nd(3+) as guest resulted in NIR-luminescent materials.