Silica effects on spectral and photophysical properties of rhodamine 6G in polyurethane matrix

Abstract

The organo-inorganic nanocomposite based on rhodamine 6G with xanthene dye and polyurethane acrylate doped with silicon dioxide has been developed. Spectral and photophysical properties of the dye in the polymer matrix have been investigated in the dependence on the concentration of SiO2 nanoparticles (1, 2, 4, and 8 mass. %). Aerosil concentration growth results in an increase of the R6G monomer–dimer ratio, which is seen on the absorption curves as an intensification of the spectral peak at 535 nm (a monomer state) relative to the spectral component at 505 nm (an aggregated state of the H-type). Adding the SiO2 nanoparticles to the polymer matrix enhances the dye luminescence intensity almost twice for a SiO2 concentration of 8 mass. %. This effect is caused by a decrease of the dimer luminescence reabsorption, since the dimer amount is smaller in the orga noinorganic nanocomposite, compared to the pure PUA. The photostability growth is observed for the R6G dye in the PUA polymer matrix doped with aerosil nanoparticles. Application of the organo-inorganic materials with the SiO2 concentration in polyurethane acrylate up to 8 mass % is shown to be promising for the development of efficient active elements for the dye lasers, pumped by the second harmonic of a neodymium laser.

Keywords

• aerosil
• luminescence
• photostability
• polyurethane acrylate