Enhancement of fluorescence intensity by silicon particles and its size effect.

Fluorescence-intensity enhancement of dye molecules was investigated using silicon submicron particles as a function of the particle size. Silicon particles with a size of 500 nm gave an enhancement factor up to 180. Measurement of scattering spectra revealed that the localized electric field at the particle enhances the fluorescence intensity.

One-pot facile synthesis of a concentrated Si nanoparticle solution.

A silicon nanoparticle solution (size ≅ 50 nm) with the concentration of 100 mM, which is contamination free, was synthesized using a ball milling method and was stable for 4 months without aggregation. This stability was responsible for large negative zeta potential on the surface of Si-NPs, established by milling in 2-propanol solvent.