Atomic-Layer Controlled Coatings on Particles

"This STTR focuses on developing new chemistry for coating Group IV nanocrystals primarily to enhance their luminescent properties. Research from the past decade has made it clear that the novel luminescent properties of sub-10nm silicon and germaniumnanoparticles are highly sensitive to surface states. For example, surface defects and coatings can either create energetic traps that compromise the luminescent properties and degrade the crystal photochemical stability, or dramatically enhance thephotoluminescent and electroluminescent quantum yields. InnovaLight has developed a proprietary in-situ process for synthesizing capped Group IV particles and achieving breakthrough quantum efficiencies and lifetimes. However, realization of thesematerials in commercial applications requires a better understanding of what is happening both chemically and physically on the surface. This STTR grant will explore the use of various capping agents (both organic and inorganic) to improve the optical andelectronic properties of these materials and to gain a better understanding of how reaction conditions affect interfacial bonding. The theoretical quantum efficiency for group IV particles is 100%. Characterizing and controlling the surface states is thekey element to realizing efficiencies that approach this number. The commercial application we are most excited about is lighting for the general illumination market. Solid-state lighting is said to be capable of saving $100 billion per year inelectricity, and 200 billion tons of carbon emissions per year to create it. This is an enormous gain to society. We have identified numerous other market opportunities for this technology as well, including flat panel displays, specialty lighting,biological sensors, quantum dot lasers, and novel floating gate memory structures. Thus, there is much commercial value to furthering the research on this fundamental science."