Freitas, Vania T.Lima, P. P.Ferreira, R. A. S.Carlos, L. D.Pecoraro, Édison [UNESP]Ribeiro, Sidney José Lima [UNESP]Zea Bermudez, V. de2014-12-032014-12-032014-05-01Journal Of Sol-gel Science And Technology. Dordrecht: Springer, v. 70, n. 2, p. 227-235, 2014.0928-0707http://hdl.handle.net/11449/111449Transparent monoliths and films of urea cross-linked tripodal siloxane-based hybrids (named tri-ureasils) were prepared by the sol-gel process, under controlled atmosphere (inside a glove box) and ambient conditions and their structure and optical features were compared. X-ray diffraction data point out that all the materials are essentially amorphous and Si-29 NMR reveal an increase in the condensation degree (0.97) for the hybrids prepared under controlled atmosphere relatively to that found for those prepared under ambient conditions (0.84-0.91). The tri-ureasils are white light emitters under UV/Visible excitation (from 250 to 453 nm) being observed for the composites prepared inside the glove box a significant enhancement (60-80 %) of the absorption coefficient and higher emission quantum yield values (similar to 0.27 and similar to 0.20 for monoliths and films, respectively) relatively to those synthesized under ambient condition.227-235engTripodal organic-inorganic hybridsTri-ureasilsSol-gelPhotoluminescenceLaboratory controlled atmosphereArtigo10.1007/s10971-013-3244-xWOS:000335639600009Acesso restrito64460474630346545282584912774370000-0003-3286-94400000-0002-5049-8797