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Abstract Molecular orientation plays a critical role in controlling carrier transport in organic semiconductors (OSCs). However, this aspect has not been explored for surface doping of OSC thin films. The challenge lies in lack of methods to precisely modulate relative molecular orientation between the dopant and the OSC host. Here, the impact of molecular orientation on dopant–host electronic interactions by large modulation of conjugated polymer orientation via solution coating is reported. Combining synchrotron‐radiation X‐ray measurements with spectroscopic and electrical characterizations, a quantitative correlation between doping‐enhanced charge carrier mobility and the Herman's orientation parameter is presented. This direct correlation can be attributed to enhanced charge‐transfer interactions at host/dopant interface with increasing face‐on orientation of the polymer. These results demonstrate that the surface doping effect can be fundamentally manipulated by controlling the molecular orientation of the OSC layer, enabling optimization of carrier transport.
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This content will become publicly available on November 7, 2025
Response of a thin coating of a porous elastic material whose generalised Young’s modulus depends on the density
Mechanics of a thin elastic coating is analysed using nonlinear constitutive relations based on the concept of a density-dependent Young’s modulus. In contrast to previous considerations on the subject, the proposed framework does not assume weak nonlinearity. Two-term asymptotic expansions are derived for four setups of boundary conditions along the upper face of the coating; in doing so, the lower face is supposed to be clamped. Explicit approximate formulae obtained in the paper have the potential to be implemented in diverse industrial applications related to thin porous coatings.
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- Award ID(s):
- 2307563
- PAR ID:
- 10554211
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Mathematics and Mechanics of Solids
- ISSN:
- 1081-2865
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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