High-quality conjugated polymers via one-pot Suzuki-Miyaura homopolymerizationZhou, D., Doumon, N. Y., Abdu-Aguye, M., Bartesaghi, D., Loi, M. A., Koster, L. J. A., Chiechi, R. C. & Hummelen, J. C. 2017 In : RSC Advances. 7, 44, p. 27762-27769 8 p.
Research output: Scientific - peer-review › Article
This paper describes a one-pot Suzuki-Miyaura homopolymerization that involves in situ borylation/cross coupling of dibrominated donor-acceptor conjugated macromonomers, in contrast to the standard Stille copolymerization of thienosilole and isoindigo monomers. Reaction kinetics investigation reveals that bis(pinacolato) diboron promotes an efficient polymerization. The homopolymer showed blue-shifted absorption compared to the Stille copolymer, which is rationalized by quantum chemical calculations of a series of oligomers containing various donor-acceptor configurations. The calculations suggest that the homopolymerization of asymmetrical macromonomers likely introduced both acceptor-acceptor and donor-donor segments into the backbone. The acceptor-acceptor segment is found to contribute mostly to the blue-shift of maximum absorption wavelength. Furthermore, detailed analysis of MALDITOF ( matrix-assisted laser-desorption ionization-time of flight) spectra of these two polymers indicated that while the homopolymer is well defined, the Stille copolymer is end-capped mostly with the thienosilole moieties and/or methyl groups, implicating that destannylation and methyl transfer are the most-likely chain-termination pathways that limit high molecular weight. This is in sharp contrast to the homopolymerization, where chain-terminators are required to control the molecular weight for obtaining soluble material. The photovoltaic performances of bulk-heterojunction solar cells based on these polymers are compared.
|Number of pages||8|
|State||Published - 2017|
- ORGANIC SOLAR-CELLS, MASS-SPECTROMETRY, COUPLING REACTION, PERFORMANCE, DERIVATIVES, COPOLYMERS