Molecular engineering of conjugated copolymers for photoactive layer in polymer solar cells
Journal
ACS National Meeting Book of Abstracts
Date Issued
2010-12-01
Author(s)
Abstract
In this work, two different strategies of molecular engineering were adopted to develop new conjugated polymers used in photoactive layers of polymer solar cells. First, low band gap copolymers contained strong electron-withdrawing 2,3-dialkylthieno[3,4-b]pyrazine(ATP)with intramolecular donor-acceptor structure were synthesized to enhance the light harvesting. These polymers showed reasonable high molecular weight (∼20000-30000 Dalton) and good solubility in organic solvents. The lowest optical band gap was 1.34eV. The second approach was the use of rod-coil block copolymers containing a conjugated segment for morphology enhancement because they might self-assemble into well-defined microphase separated morphologies which can provide excitons with large donor/acceptor interfaces for charge separation and interconnected pathways for charge carrier transportation. A feasible method was developed to synthesize P3HT block copolymers with accurately controlled compositions and molecular weights via the coupling reaction between aldehyde end-functionalized P3HT and polymeric anions. The morphologies and photophysical properties of these block copolymers were found to be affected by the chemical structures and molecular weights of the coil segment.
Type
conference paper