Conjugated polymers are one of the leading technologies in electronic materials research. In this work we investigate thiophene-based donor-donor (D-D) and donor-acceptor (D-A) conjugated oligomers for future application towards polymer solar cells (PSCs).
Beginning from computational studies, our group targets specific monomers that show promise in both bandgap and solar cell efficiency. For this research, we have found a novel alkyl-nitrothiophene (2-bromo-5-cyano-3-hexyl-4-nitrothiophene, NT) monomer as well as a unique D-D combination of propylenedioxythiophene (ProDOT) and isothianapthene (ITN). In both of these cases, we found that we can tune the tetramer bandgap (in both D-D and D-A systems) simply by changing the order of monomers (rather than changing the identity of the monomers). Horner-Wadsworth-Emmons (HWE) was chosen to provide the ability to individually couple monomers, allowing us to synthesize sequenced oligomers.
The synthesis of the novel alkyl-NT monomer was successful and progress towards additional monomers necessary for HWE coupling was made. A test Stille coupling towards the synthesis of the ProDOT-ITN oligomer was also attempted
