A new ESIPT fluorescent dye-doped silica aerogel

Abstract

A silyl-functionalized benzazole dye, fluorescent by excited state intramolecular proton transfer (ESIPT) mechanism, was synthesized by reacting 2-(2′-hydroxyphenyl)benzoxazole with 3-(triethoxysilyl)propyl isocyanate. The fluorescent silica gel was prepared by the addition of a solution of 2-propanol and the fluorescent dye after the gelation time. The monolithic aerogel was obtained via supercritical CO2 drying of the fluorescent gel. The resulting aerogel is transparent in the visible light and fluorescent in the blue-green region under UV radiation. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.