Novel Mechanisms to Tune Electronic Characteristics in Small-Molecule Organic Semiconductors

Abstract

The Haley Lab is interested in the synthesis and characterization of organic hydrocarbon scaffolds which can be used as semiconductors. The family of indenofluorene hydrocarbons exhibit unique electronic properties such as antiaromaticity and diradical character, which contribute to their allure for scientists. Specifically, our studies into indenofluorenes have shown promise in regard to the ability of these molecules to serve as potential replacements for current inorganic counterparts within devices. Continuous fundamental studies into the electronic abilities of these molecules will help to elucidate the ideal characteristics of organic semiconductors, which is imperative for the feasible implementation of these molecules into devices. Our lab has developed highly modular synthetic routes toward many analogues of this parent scaffold, which can be further optimized through subtle synthetic tuning. Fusing a variety of aryl moieties onto the parent scaffold allows for a decrease in the HOMO-LUMO energy gap and subsequent improvement in electron mobility and conductivity. Our project initially focused on proving the diradical character in an analogue of indenoindenodibenzothiopene, and has successfully shown this by reacting the molecule through a known radical degradation pathway. This project is now focused on the optimization of previous synthetic routes such that further studies into these highly interesting molecules can be carried out. Our goal is to create a library of analogues with various electronic characteristics such that we may identify the most promising candidates for device implementation.