Photoluminescence of silicon nanoparticles chemically modified by alkyl groups and dispersed in low-polar liquids

A detailed comparative analysis of photoluminescence behavior of silicon nanoparticles in air and dispersed in low-polar liquids is reported. Efficient dispersion and excellent stability of the chemically modified nanoparticles in low-polar liquids are achieved. Influence of the chemical functionalization and of the low-polar liquids on steady-state and time-resolved photoluminescence of the silicon nanoparticles is investigated. Role of low-polar liquids on recombination mechanisms taking place in the nanoparticles is discussed in terms of Forster resonant energy transfer processes. Effect of exciting laser power on photoluminescence spectra of the silicon nanoparticles both in air and in low-polar liquids is investigated and the electronic mechanisms involved into the observed phenomena are discussed.