Study of the structural analysis of dye-silica core-shell nanoparticles (DSCSNPs)

The core-shell structure of dye-silica nanoparticles have been successfully prepared by incorporation of fluorescent coumarin 445 dye inside the silica network by subsequent sol-gel reaction of dye-silane and tetraethylorthosilicate (TEOS). The characteristic of DSCSNPs have been studied by TEM, SEM, AFM, XRD, DLS, analysis. Structural studies revealed the formation of three groups of samples, (1) dense (coumarin dye core / silica shell) nanoparticles, (2) dense coumarin dye core / porous silica shell nanoparticles were spherical in shape and the size was about 100 nm that agreed with DLS results, (3) hollow silica particles is spherical and have sizes 10nm in diameter. The x-ray diffraction pattern of DSCSNPs thin film shows hexagonal structure with crystallite size 30 nm.