Research conducted in our laboratory focuses on the general field of advanced materials, with a particular focus on the areas of conductive polymers and novel organic electronic materials. We combine synthetic chemistry with materials characterization and computational chemistry to design and comprehensively study organic electronic materials (Scheme 1). Special emphasis is placed on applying physical organic chemistry tools to materials chemistry research. We believe that the two research directions of greatest current importance in this field are the design and synthesis of new materials and improving understanding of the properties of existing materials. Our group is therefore working mainly in these two directions.

  Our research approach has proven effective and has led to significant results, particularly in the areas of polyselenophene and oligofuran chemistry. Polythiophenes are the most studied type of conducting polymer and the subject of thousands of papers. Various types of polythiophene-based materials have been proposed as conductors, electrode materials, organic semiconductors, and materials with nonlinear optical properties. Polyselenophene is expected to retain a number of the characteristics of the sulfur-based polymer, while being superior to it for some applications. Despite their potential advantages, polyselenophenes have attracted surprisingly scant attention. Previous reports (before our recent 2008 paper) suggested that the conductivity of doped polyselenophene was at least three orders of magnitude lower than that of the analogous polythiophene, which effectively silenced selenophene research. Only one earlier study described the preparation of a conductive polyselenophene. However, the reported conductivity of 0.1 S/cm was still ~2 orders of magnitude lower than that of the parent polythiophene. We succeeded in synthesizing the first highly conductive polyselenophene, so opening a new sub-field in materials science that we are now actively engaged in developing.

  Stability, good solid state packing, processability, rigidity/planarity, high fluorescence, and a HOMO–LUMO gap in the semiconductor region (which also leads to absorption/emission in the visible range) are among the main requirements for useful organic electronic materials. Among the workhorses in this field are long α-oligothiophenes (in particular α-sexithiophene, 6T) and oligoacenes (in particular, pentacene). These materials have been extensively studied and employed in organic field effect transistors (OFETs) due to their superior electronic properties, including relatively high field effect mobility. There is an ongoing search for new compounds possessing most of the advantages of oligo- and polythiophene, but with enhanced fluorescence, solubility, and rigidity. Yet, long α-oligofurans (such as sexifuran), which are close oligothiophene analogues, were unknown before our recent 2010 paper and even short α-oligofurans were never structurally characterized. It has been suggested that α-oligofurans comprising more than four rings are unstable since they are very electron rich, and the longest substituted α-oligofuran consists of five rings. Nevertheless, we succeeded in synthesizing and characterizing a series of unsubstituted α-oligofurans containing up to nine rings and possessing reasonable stability. Usually, organic electronic materials are not biodegradable, and extensive usage of these compounds may generate a significant amount of hazardous waste. It is therefore significant that furan-only containing materials are biodegradable, and (in contrast to other types of conjugated materials) furans can be obtained from entirely renewable resources.

  Our group devotes significant efforts to applications of modern computational chemistry tools to problems in the areas of organic electronic materials and mechanistic organic chemistry, in order to increase scientific understanding of these fields. Much of our computational work is devoted to understanding the correlation between various properties and chain length.