Model of the formation of dibenzoylmethanatoboron difluoride exciplexes with aromatic hydrocarbons on silica surface

Abstract

Dibenzoylmethanatoboron difluoride (DBMBF2) is a fluorophore capable of forming exciplexes with benzene and its derivatives in solutions [1] or in the adsorbed state on the silica gel surface by reacting with vapor of these substances [2, 3], a property that may be used for the fabrication of highly selective and responsive sensor devices. In this study, the dependence of the fluorescence spectra of silica-supported DBMBF2 samples on the vapor concentration of the aromatic compounds benzene, toluene, and p-xylene has been examined. A model describing the observed spectral changes has been proposed. The data on the concentration dependence of the fluorescence spectra of silica gel microspheres bearing adsorbed DBMBF2 are in good agreement with the proposed model.