Abstract
The ability of organic electronics to maintain stability at elevated temperatures is crucial for the longevity of optoelectronic devices. However, achieving stable optoelectronic properties for conjugated polymers remains fundamentally challenging. Here, we identify backbone twisting motion as the primary reason for the unstable optoelectronic properties of donor-acceptor (D-A) conjugated polymers, using diketopyrrolopyrrole (DPP)-based polymers as a model system. The backbone thiophene-ring twist transition is responsible for shifts in the band gap and alterations in charge transport properties. The twisting motion of the thiophene induces localization of the intrachain electrons, resulting in reduced charge carrier mobility and a significant blue shift in optical absorption. Additionally, we demonstrated that intramolecular hydrogen bonding interaction within DPP polymers can suppress undesired backbone twisting at elevated temperatures, thereby ensuring a more stable optoelectronic property. Our work offers fundamental insights into the decline in device stability at elevated temperatures and a strategy to enhance device stability.
| Original language | English |
|---|---|
| Article number | 102195 |
| Journal | Matter |
| Volume | 8 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 1 2025 |
Funding
This work was supported by the Office of Naval Research under contract no. N00014-23-1-2063 for thermal stability and device characterization. We also thank the U.S. Department of Energy, Office of Science, Office of Basic Energy Science , under award no. DE-SC0022050 for enabling neutron scattering measurements. Part of the research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Z.L., S.A.T., and W.X. acknowledge support from the National Science Foundation under awards 2237063 and 2119691 . S.R.-G. thanks the Natural Sciences and Engineering Research Council of Canada for financial support through a Discovery Grant ( RGPIN-2017-06611 ). A.A. thanks the Province of Ontario and the University of Windsor for financial support through an Ontario Graduate Scholarship . M.M. thanks NSERC for financial support through a Canada Postgraduate Doctoral Scholarship . This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The beam time was allocated to BASIS on proposal number IPTS-26235.1. The authors thank Naresh Osti from SNS, ORNL, for assistance during the QENS experiments. We thank Dr. Jianguo Mei from Purdue University for the fruitful discussion of this work.
Keywords
- MAP 3: Understanding
- chain dynamics
- charge transport
- conjugated polymers
- device stability
- optoelectronic property