Donor – acceptor and donor – donor alternating conjugated polymers based on dithieno[3,2-b:2',3'-d]pyrrole: synthesis, optical properties and organic solar cells applications

In this paper, two novel donor–acceptor (D-A) and donor-donor (D-D) conjugated polymers containing dithieno[3,2-b:2',3'-d]pyrrole in combined respectively with thieno[3,4-c]pyrrole-4,6-dione and benzo[1,2-b:4,5-b']dithiophene derivatives were synthesized successfully via direct (hetero) arylation polymerization where the Pd(OAc) 2 and PCy 3 .HBF 4 have been used as the catalyst system. The obtained conjugated copolymers have been characterized via FT-IR, GPC, 1 H NMR and XRD to determine the chemical structures, chemical compositions as well as the macromolecular characteristic features. In addition the conjugated polymers have been investigated for the optical and thermal properties including UV–Vis, fluorescent emission, DSC and TGA respectively. The electrochemical properties of the conjugated polymers have been evaluated via cyclic voltammetry to determine the HOMO–LUMO energy levels which are suitable for organic solar cells devices.