Preparation of luminescent Si nanocrystals from rice husks

Abstract

Luminescent Si nanocrystals were prepared from rice husks and the optical properties and structure analysis were studied. By the transmission electron microscope observation of the Si powder from rice husks, aggregates that are composed of Si nanoparticles with crystalline structure were confirmed. Room temperature PL with near infrared-red regions were observed from the Si nanocrystals. From the measurements of the PL decay curves, order of the life time were sub-micro seconds and that depended on the wavelength of the luminescence. These results indicates that the origin of the PL from Si nanocrystals made from rice husks is quantum size effect. Preparation of luminescent Si nanocrystals from rice husks is an effective method for recycling rice husks.