MRSEC Seminar

Novel Types of Organic Electronic Materials: Polyselenophenes and Oligofurans

Michael Bendikov

Department of Organic Chemistry
Weizmann Institute of Science

Tuesday, April 13, 2010 at 2:00 p.m.

Tech K140

Despite the diverse applications of conducting polymers, only a limited number of conducting polymer families has been developed. We have developed a family of conducting polymers, namely polyselenophenes. In particular, we have developed new, general and efficient synthetic strategy for the preparation of poly(3,4-ethylenedioxyselenophene) (PEDOS), the first highly conductive polyselenophene. We have also obtained several other types of the polyselenophenes, some of which show very remarkable properties. Our extensive characterizations of PEDOS and other polyselenophenes reveal that they are highly conductive, electrochemically active, very stable and having bandgap, lower than their polythiophene analogs. PEDOS derivatives are excellent electrochromic materials which are very transparent in the doped state and are currently among the best electrochromic materials reported.  In our initial work developing this area, we have taken advantage of the fact that parent polyselenophenes have a lower bandgap than parent polythiophenes to design polyselenophenes appropriate for application in organic solar cells.
Long α-oligothiophenes (in particular α-sexithiophene) and oligoacenes (in particular, pentacene) have been extensively studied. Yet, while oligothiophenes are intensively studied, their close analogs, long α-oligofurans (1) were not known. In this lecture I will discuss the synthesis and characterization of a series of long unsubstituted α-oligofurans (up to n=9). Interestingly, α-oligofurans (compared to oligothiophenes and alternating furan-thiophene oligomers) are highly fluorescent, exhibit very good solid state packing, high rigidity, and better solubility than oligothiophenes.

Host: Professor Tobin Marks, MSE