Synthesis and optical characterization of silicon nanoparticles

Various reaction conditions, such as quantity of reducing agent and reaction time were investigated with the aim of finding a simple, optimized synthetic route for the synthesis of luminescent silicon nanoparticles (SiNPs). Si NPs were synthesized from the reaction of ethylenediammonium chloride and magnesium silicide via a low temperature solution route. Optical characterizations of silicon nanoparticles were achieved by using ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy. As the reaction time longer, silicon nanoparticles grew and their emission wavelength shifted to the longer wavelength. The monotonic shift of the photoluminescence as a function of excitation wavelength resulted in the excitation of different sizes of nanocrystals that had different optical transition energies.