Abstract
The true structure of alternating conjugated polymers—the state-of-the-art materials for many organic electronics—often deviates from the idealized picture. Homocoupling defects are in fact inherent to the widely used cross-coupling polymerization methods. Nevertheless, many polymers still perform excellently in the envisaged applications, which raises the question if one should really care about these imperfections. This article looks at the relevance of chemical precision (and lack thereof) in conjugated polymers covering the entire spectrum from the molecular scale, to the micro and mesostructure, up to the device level. The different types of polymerization errors for the alkoxylated variant of the benchmark (semi)crystalline polymer poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene (PBTTT) are identified, visualized, and quantified and a general strategy to avoid homocoupling is introduced. Through a combination of experiments and supported by simulations, it is shown that these coupling defects hinder fullerene intercalation and limit device performance as compared to the homocoupling-free analog. This clearly demonstrates that structural defects do matter and should be generally avoided, in particular when the geometrical regularity of the polymer is essential. These insights likely go beyond the specific PBTTT derivatives studied here and are of general relevance for the wider organic electronics field.
| Original language | English |
|---|---|
| Article number | 2309403 |
| Number of pages | 11 |
| Journal | Advanced Functional Materials |
| Volume | 33 |
| Issue number | 52 |
| DOIs | |
| Publication status | Published - 22 Dec 2023 |
Bibliographical note
Funding Information:The authors thank the FWO Vlaanderen (Ph.D. and travel grant J.V. (1S50822N and V413722N), projects G0D0118N and G0B2718N, MALDI-ToF project I006320N, DUBBLE project I001919N, Scientific Research Community “Supramolecular Chemistry and Materials” ‒ W000620N) and the European Research Council (grant 864625) for financial support. J.V. received a personal grant from District 1630 of Rotary International, supported by the Rotary Foundation, allowing a student researcher to visit Stanford University. X.W. acknowledges co-funding from the European Union's Horizon 2020 research and innovation Marie Skłodowska-Curie Actions, under grant agreement no. 945380. Q.L. acknowledges financial support from the European Union's Horizon 2020 research and innovation program under the Marie-Curie grant agreement no. 882794. The IMEC and UMons authors acknowledge funding from the European Commission Horizon 2020 Future and Emerging Technologies project MITICS (964677). D.B. is a FNRS Research Director. T.J.Q. acknowledges support from the National Science Foundation Graduate Research Fellowship Program under grant DGE-1656518. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists, Office of Science Graduate Student Research (SCGSR) program. The SCGSR program is administered by the Oak Ridge Institute for Science and Education for the DOE under contract number DE-SC0014664. Use of the Stanford Synchrotron Radiation Light source, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF)/Stanford Nanofabrication Facility (SNF) supported by the National Science Foundation under award ECCS-2026822 and the Stanford SIGMA Facility with support from the Stanford Doerr School of Sustainability.
Funding Information:
The authors thank the FWO Vlaanderen (Ph.D. and travel grant J.V. (1S50822N and V413722N), projects G0D0118N and G0B2718N, MALDI‐ToF project I006320N, DUBBLE project I001919N, Scientific Research Community “Supramolecular Chemistry and Materials” ‒ W000620N) and the European Research Council (grant 864625) for financial support. J.V. received a personal grant from District 1630 of Rotary International, supported by the Rotary Foundation, allowing a student researcher to visit Stanford University. X.W. acknowledges co‐funding from the European Union's Horizon 2020 research and innovation Marie Skłodowska‐Curie Actions, under grant agreement no. 945380. Q.L. acknowledges financial support from the European Union's Horizon 2020 research and innovation program under the Marie‐Curie grant agreement no. 882794. The IMEC and UMons authors acknowledge funding from the European Commission Horizon 2020 Future and Emerging Technologies project MITICS (964677). D.B. is a FNRS Research Director. T.J.Q. acknowledges support from the National Science Foundation Graduate Research Fellowship Program under grant DGE‐1656518. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists, Office of Science Graduate Student Research (SCGSR) program. The SCGSR program is administered by the Oak Ridge Institute for Science and Education for the DOE under contract number DE‐SC0014664. Use of the Stanford Synchrotron Radiation Light source, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE‐AC02‐76SF00515. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF)/Stanford Nanofabrication Facility (SNF) supported by the National Science Foundation under award ECCS‐2026822 and the Stanford SIGMA Facility with support from the Stanford Doerr School of Sustainability.
Publisher Copyright:
© 2023 The Authors. Advanced Functional Materials published by Wiley-VCH GmbH.
Keywords
- homocoupling
- intermolecular charge-transfer absorption
- polymer:fullerene co-crystals
- Stille cross-coupling
- structural defect quantification