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Updated: Dec 11, 2025
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Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
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Orientation-Dependent Host-Dopant Interactions for Manipulating Charge Transport in Conjugated Polymers
Fengjiao Zhang1, Erfan Mohammadi2, Ge Qu2
1School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
Advanced Materials (Deerfield Beach, Fla.)
|August 20, 2020
Summary
Controlling molecular orientation in organic semiconductors (OSCs) significantly enhances surface doping effects. Optimizing polymer orientation improves charge carrier mobility by strengthening dopant-host interactions.
Area of Science:
- Materials Science
- Organic Electronics
- Semiconductor Physics
Background:
- Molecular orientation is crucial for charge transport in organic semiconductors (OSCs).
- Methods for controlling relative molecular orientation between dopants and OSC hosts are lacking.
- Surface doping effects in OSC thin films remain underexplored concerning molecular orientation.
Purpose of the Study:
- To investigate the impact of molecular orientation on dopant-host electronic interactions in OSCs.
- To establish a quantitative correlation between molecular orientation and doping-enhanced charge carrier mobility.
- To demonstrate the manipulation of surface doping effects by controlling OSC molecular orientation.
Main Methods:
- Large-scale modulation of conjugated polymer orientation using solution coating techniques.
- Synchrotron-radiation X-ray measurements to determine molecular orientation (Herman's orientation parameter).
- Spectroscopic and electrical characterizations to assess doping effects and charge carrier mobility.
Main Results:
- A direct quantitative correlation was found between doping-enhanced charge carrier mobility and the Herman's orientation parameter.
- Increased face-on orientation of the polymer enhances charge-transfer interactions at the host/dopant interface.
- Molecular orientation significantly impacts the effectiveness of surface doping in OSCs.
Conclusions:
- Surface doping in organic semiconductors can be fundamentally controlled by manipulating the molecular orientation of the OSC layer.
- Optimizing molecular orientation provides a pathway for enhancing charge carrier transport in doped OSCs.
- This work opens avenues for designing high-performance organic electronic devices through precise orientation control.
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