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Updated: Jul 24, 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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Adsorption Structures Affecting the Electronic Properties and Photoinduced Charge Transfer at Perylene-Based
Sara Wirsing1, Marc Hänsel2, Luca Craciunescu1
1Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Emil-Fischer-Straße 42, 97074, Würzburg, Germany.
Chemistry, an Asian Journal
|July 10, 2023
Summary
Organic semiconductors facilitate charge transfer at interfaces, crucial for electronic devices. This study reveals how molecular geometry influences ultrafast charge transfer dynamics in perylene-based materials, impacting device performance.
Area of Science:
- Organic electronics
- Photophysics
- Materials science
Background:
- Perylene-based organic semiconductors are key components in organic electronic devices.
- Understanding excited state dynamics at donor-acceptor interfaces is vital for optimizing device efficiency.
Purpose of the Study:
- To investigate ultrafast excited state dynamics at diindenoperylene (DIP) and dicyano-perylene-bis(dicarboximide) (PDIR-CN2) interfaces.
- To elucidate the role of interfacial molecular geometry in charge transfer (CT) processes.
- To correlate interfacial structure with charge transfer dynamics using experimental and theoretical methods.
Main Methods:
- Femtosecond time-resolved second harmonic generation (SHG) spectroscopy.
- Large-scale quantum chemical calculations.
- Fabrication and analysis of DIP/PDIR-CN2 bilayer structures with varied interfacial geometries.
Main Results:
- Optically induced charge transfer (CT) was observed in interfacial configurations with mixed edge-on and face-on geometries, indicated by a SHG signal increase.
- The interfacial CT state exhibited a decay time of 7.5±0.7 ps, with hot CT states decaying faster (5.3±0.2 ps).
- Interfacial CT formation was suppressed in structures with predominantly edge-on geometries due to limited perpendicular π-π overlap.
Conclusions:
- Interfacial molecular geometry significantly dictates charge transfer dynamics in perylene-based organic semiconductors.
- Specific interfacial configurations, including face-on domains, promote efficient charge transfer.
- Insights into D/A charge transfer properties are crucial for advancing the interfacial photophysics of organic electronic materials.
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