Bin Haijun, Li Junyu, Caiazzo Alessandro, Wienk Martijn M, Li Yongfang, Janssen René A J
Laboratory of Advanced Optoelectronic Materials, Suzhou Key Laboratory of Novel Semiconductor Materials and Devices, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, Jiangsu, P. R China.
Molecular Materials and Nanosystems & Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, 5600 MB (The, Netherlands.
ChemSusChem. 2023 Mar 22;16(6):e202300006. doi: 10.1002/cssc.202300006. Epub 2023 Jan 23.
Creating new donor materials is crucial for further advancing organic solar cells. Random terpolymers have been adopted to overcome shortcomings of regular alternating donor-acceptor (D-A) polymers of which the performance is often susceptible to batch-to-batch variations. In general, the properties and performance of efficient D -A-D -A and D-A -D-A terpolymers are sensitive to the D /D or A /A monomer ratios. Side-chain hybridization is a strategy to address this problem. Here, six D -A-D -A-type random terpolymers comprising D and D monomers with the same π-conjugated D unit but with different side chains were synthesized. The side chains, containing either fluorine or trialkylsilyl substituents were chosen to provide near-identical optoelectronic properties but provide a tool to create a better-optimized film morphology when blended with a non-fullerene acceptor. This strategy allows improving the device performance to over 18 %, higher than that obtained with the corresponding D -A or D -A bipolymers (around 17 %). Hence, side-chain hybridization is a promising strategy to design efficient D -A-D -A terpolymer donors that are insensitive to the D /D monomer ratio, which is beneficial for the scaled-up synthesis of high-performance materials.
