New Surface Chemistries and Process Innovations in the Production of Surface Functionalized Semiconductor Nanoparticles

Tulane University, New Orleans LA

Investigators

Abstract

Silicon nanoparticles with alkyl-functionalized surfaces formed by mechanochemical methods are the focus of these investigations. In the mechanochemical process, silicon is comminuted in size using mechanical attrition in the presence of a reactive organic liquid. As fresh surface silicon atoms are exposed in the comminution process, they react with the organic medium to create functionalized nanoparticles. The scientific merit of the research lies in three specific goals: 1) to extend the concept to new chemistries including alkynes, alkenes, and dienes and their heteroatom anologues; 2) to evaluate process innovations that lead to the rapid production of uniform-sized functionalized nanoparticles via mechanochemical synthesis; and 3) to model the solubility and phase behavior of surface functionalized nanoparticles. The use of "click" chemistry will be explored as a way of increasing the complexity of the silicon surface and to create a functional architecture. New functionalized nanoparticles will be characterized primarily for their optoelectronic properties. Molecular dynamics simulations will be used to elucidate the effect of surface chain length on phase behavior and interparticle forces the lead to phase separation. Process innovations will be achieved through the study of multi-phase mechanochemical synthesis which will open new avenues to nanoparticle functionalization, separation, and production. Broader impacts include the potential applications for functionalized silicon nanoparticles in the areas of fluorescent biological staining labels, nanoparticle lasers, and solar energy. Educational and outreach activities include research experiences for undergraduates, minority participation in research projects, and international research opportunities through the German Academic Exchange Program.