Photoluminescence of Eu(III)-doped lamellar bridged silsesquioxanes self-templated through a hydrogen bonding array
authors Nobre, SS; Brites, CDS; Ferreira, RAS; Bermudez, VD; Carcel, C; Moreau, JJE; Rocha, J; Man, MWC; Carlos, LD
nationality International
journal JOURNAL OF MATERIALS CHEMISTRY
keywords ORGANIC-INORGANIC HYBRIDS; BETA-DIKETONATE COMPLEX; CARBOXYLIC-ACID SOLVOLYSIS; FULL-COLOR PHOSPHORS; LONG ALKYLENE CHAINS; WHITE-LIGHT EMISSION; X-RAY-DIFFRACTION; SOLID-STATE NMR; THIN-FILMS; LUMINESCENCE PROPERTIES
abstract An organic molecule, (EtO)(3)Si(CH(2))(3)NH(C =O) NH-(CH(2))(12) - NH(C = O) NH(CH(2))(3)Si(OEt)(3), combining urea functionalities and a 12-carbon alkyl chain, underwent sol - gel reactions in the presence of an acid catalyst, a large excess of water and variable amounts of EuCl(3), giving rise to the formation of crystalline hybrids through a self- directed organization process in which hydrogen bonding interactions play a key role. Three photoluminescent lamellar Eu(3+)- doped silsesquioxane hybrids incorporating 1.01, 1.83 and 15.04% Eu(3+) were prepared and fully characterized. The lamellar hybrids are room temperature multi-wavelength emitters due to the convolution of the hybrid's emitting centres and the Eu(3+) intra- 4f(6) transitions. Their emission colour can be easily tuned along the Commission Internationale d'Eclairage chromaticity diagram from the bluish- purple region to the pink area, either by changing the excitation wavelength or the Eu(3+) amount. The Eu(3+) first coordination shell is very similar for the three photoluminescent lamellar Eu3+- doped silsesquioxane hybrids incorporating oxygen atoms of the carbonyl group, Cl atoms and water molecules, despite the minor variations found in the (5)D(0) quantum efficiency ( 16.3 - 19.2), number of water molecules ( 1.7 - 2.0) and experimental intensity Omega(2) parameter (8.9 - 10.1 x 10(-20) cm(2)) with the increase of Eu(3+) content.
publisher ROYAL SOC CHEMISTRY
issn 0959-9428
year published 2008
volume 18
issue 35
beginning page 4172
ending page 4182
digital object identifier (doi) 10.1039/b807262k
web of science category Chemistry, Physical; Materials Science, Multidisciplinary
subject category Chemistry; Materials Science
unique article identifier WOS:000258949900008

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