Nanoscale Materials Research Laboratory
Organic semiconductor
Crystallization of specific organic molecules, such as pi-conjugated molecules, affords suitable band gap and charge carrier transport properties for semiconductors. Organic semiconductor crystals are widely used for field-effect transistors, light-emitting diodes, and solar cells. However, relatively poor charge carrier mobility restricts further application and commercialization. Our group has developed new crystallization methods to realize novel electrical and optical properties via structural and morphological alteration.
Radical crystal
With the development of high-performance organic electronics, there have been increasing efforts to use unpaired electrons (radicals) as electronic charge carriers for high electrical conductivity. In this regard, radical crystals that can form a smaller band gap than neutral crystals are fascinating. We focus on the growth of radical crystals and the development of secondary treatments for radical activation in neutral crystals.
Chemical doping
A chemical doping technique is necessary to overcome the low electrical properties of organic semiconductor materials. We are particularly focused on developing high-efficiency doping methods (solution phase doping and in-situ Raman spectroscopy and conductivity doping. Currently, fundamental research is being conducted on solvated electrons to determine the doping mechanism in a solution. Through this, we will be able to develop a new doping method that freely controls electrons according to our will.