A new solution route to hydrogen-terminated silicon nanoparticles: synthesis,functionalization and water stability

Abstract

Hydrogen-capped silicon nanoparticles with strong blue photoluminescencewere synthesized by the metathesis reaction of sodium silicide, NaSi, withNH4Br. The hydrogen-capped Si nanoparticles were further terminated with octylgroups and then coated with a polymer to render them water-soluble. Thenanoparticles were characterized by TEM, FT-IR, UV–vis absorption andphotoluminescence. The Si nanoparticles were shown to have an average diameter of3.9 ± 1.3 nm and exhibited room temperature photoluminescence with a peak maximum at 438 nmwith a quantum efficiency of 32% in hexane and 18% in water; the emission wasstable in ambient air for up to 2 months. These nanoparticles could hold greatpotential as a non-heavy-element-containing quantum dot for applications in biology.