Nano-assembly and optical properties of difluoroboron dibenzoylmethane-polysilane

Abstract Aggregation of various fluorophores is a useful approach to build highly sensitive and selective fluorescent sensors. In this work, the ability of oligomeric polydiphenylsilanes to associate with fluorescent low molecular weight organic compound is illustrated by the formation of stable aggregates between poly[diphenyl-co-methyl(H)]silane and dibenzoylmethanatoboron difluoride in solution. The formation of these nano-structures in solution was investigated both experimentally using gel permeation chromatography, σ spectroscopy and fluorescence spectroscopy, and theoretically by molecular modeling. Thin films obtained from this solution have a characteristic morphology in which the nano-aggregates undergo a self-organizing process and form crystalline spherulites. Association between the fluorescent polysilane and the fluorescent diketonato boron complex proceeds with an increase of fluorescence (amplification efficiency up to 90%) through a FRET mechanism as a result of aggregation, a phenomenon that could be used in the development of fluorescent sensors.