Orientation‐Dependent Host–Dopant Interactions for Manipulating Charge Transport in Conjugated Polymers
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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 18, 2020
- Source ID
- 10.1002/adma.202002823
Entities
People
- Erfan Mohammadi
- Fengjiao Zhang
- Ge Qu
- Xiaojuan Dai
- Ying Diao
Organizations
- Institute of Chemistry
- National Science Foundation
- Office of Naval Research
- University of Chinese Academy of Sciences
- University of Illinois Urbana–Champaign