Herein, we describe the synthesis and characterization of a conjugated donor–acceptor copolymer consisting of a pyrrolopyridazinedione (PPD) acceptor unit, and a benzodithiophene (BDT) donor unit. The polymerization was done via a Stille cross-coupling polycondensation. The resulting PPD–BDT copolymer revealed an optical bandgap of 1.8 eV and good processability from chlorobenzene solutions. In an organic solar cell in combination with PC70BM, the polymer led to a power conversion efficiency of 4.5%. Moreover, the performance of the copolymer was evaluated in polymer/nanocrystal hybrid solar cells using non-toxic CuInS2 nanocrystals as inorganic phase, which were prepared from precursors directly in the polymer matrix without using additional capping ligands. The PPD–BDT/CuInS2 hybrid solar cells showed comparably high photovoltages and a power conversion efficiency of 2.2%.Graphical abstract
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: Open access funding provided by Austrian Science Fund (FWF). A.-C. K. and T. R. gratefully acknowledge the financial support from the Austrian Science Fund (FWF) via Grants T578-N19 and J3515-N20. The authors thank Sergey Borisov for helpful discussions, the Elettra synchrotron for the allocation of beamtime on the XRD1 beamline and Luisa Barba for experimental support.