Method of improving photoluminescence of silicon nanoparticles

A method of improving the photoluminescence of silicon nanoparticles is provided along with a description of the silicon nanoparticle compositions prepared therefrom. The method generally comprises exposing a composition comprising silicon nanoparticles having a mean particle diameter not greater than 5 nm and a fluid to a non-ambient condition selected from (i) elevated temperature, (ii) elevated humidity, (iii) elevated pressure exerted by an oxygen-containing gas, (iv) a hydrogen plasma, (v) hydrogen gas, (vi) ultraviolet radiation, and (vii) and a combination of at least two of (i)-(vi). Optionally, the silicon nanoparticles may be prepared by a gas phase reaction. The exposure of the silicon nanoparticle compositions to the non-ambient condition results in improved photoluminescence. In particular, the exposed nanoparticles exhibit increased maximum emission intensity and luminescent quantum efficiency. Moreover, these improvements are accompanied by a blue shift in the emitted light to a shorter wavelength.