Rhodamine B-anchored silica nanoparticles displaying white-light photoluminescence and their uses in preparations of photoluminescent polymeric films and nanofibers.

This work reports white-light photoluminescent (PL) silica nanoparticles and their applications of preparation of PL polymer films and nanofibers. Rhodamine B (RhB) physically adsorbs or chemically bonds to silica nanoparticle (SNP) surfaces, resulting in PL SNPs. The RhB-modified SNPs exhibit white-light PL emissions under an excitation at 365nm, which is different from the inherent yellow light emission of RhB. The SNPs with physically-adsorbed RhB show stimuli-responsive properties. In solutions, the RhB molecules which physically adsorb to SNPs release from SNPs, consequently turning the PL emission from white-light to yellow. On the other hand, the SNPs having covalently-bonded-RhB molecules are effective additives for preparation of white-light PL polymer composites. Both PL poly(methylmethacrylate) (PMMA) films (from casting process) and nanofibers (from electrospinning process) showing white-light PL emission have been prepared.