Polymer-coated silicon nanoparticle synthesis for optical applications

Currently, silicon nanoparticles (SiNPs) are of great interest due to their potential applications in various fields such like optoelectronics, microelectronics, photonics, photovoltaics, chemical, and biologic sensors. SiNPs Become the most important and well-known semiconductor because Si-based devices have dominated microelectronics for many decades. Indeed, the production of smart SiNPs materials to enhance absorption and light scattering is currently the most convenient approach. Recently, plasmonic fractal-like structures have been determined to enhance photovoltaic device performances; indeed, through an efficient coupling of the incident light at different frequency bands into both the surface plasmon modes and the cavity modes, a broadband absorption enhancement can be accomplished. Silicon nanoparticles exhibit fluorescence deriving from Si quantum dot structures which are produced during chemical etching, and it can be synthesized with unique optical reflectivity spectra. These unique characteristics allow porous silicon to exhibit a signal that is affected in a expected way when exposed to environmental changes, presenting possibilities for the development of advanced functional systems that incorporate sensors for therapeutic functions or diagnostic. In order to prevent rapid degradation after administration and to increase their blood half life, biocompatible polymers coating was performed on silicon nanoparticles. Different type of biocompatible polymers (chitosan, polylactic acid, PMMA, or dextran,) can be used. However, several methods have been developed for the synthesis of silicon nanoparticles such as chemical etching, sol-gel technique, laser ablation, sputtering process; hot-wire synthesis, ball milling process, and microemulsion. The main objective of this research is to develop a new technique for coating or encapsulation of Nanoparticles to modify their surface properties by using different polymers. Furthermore, polymers are non-toxic, non-flammable, relatively inexpensive and recyclable.