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Updated: May 14, 2026
11:33
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Supramolecular Modulation of Photoinduced Charge Transfer: Tuning Between Tunneling and Incoherent Hopping
Xueze Zhao1, Guangcheng Wu1, Chun Tang1
1Department of Chemistry, The University of Hong Kong, Hong Kong SAR, China.
Angewandte Chemie (International Ed. in English)
|May 12, 2026
Summary
Harnessing molecular recognition, this study offers unprecedented control over photoinduced charge transfer (CT) dynamics in supramolecular systems. This approach enhances charge separation and reduces recombination, paving the way for advanced artificial light-harvesting materials.
Area of Science:
- Supramolecular Chemistry
- Photochemistry
- Materials Science
Background:
- Photoinduced charge transfer (CT) is crucial for photosynthesis and solar energy.
- Traditional donor-bridge-acceptor (D-B-A) systems face challenges in CT control due to synthesis and tunability limitations.
- Molecular recognition offers a promising alternative for regulating CT dynamics.
Purpose of the Study:
- To investigate the use of molecular recognition for precise control over photoinduced charge transfer (CT) processes.
- To explore the modulation of charge separation and recombination rates within supramolecular complexes.
- To demonstrate a novel strategy for designing advanced light-harvesting materials.
Main Methods:
- Integration of guest molecules with varying frontier orbital energies into a rigid cyclophane host (DAPPTTzBox4+).
- Utilizing cofacially stacked chromophores for directional intramolecular CT.
- Analyzing CT mechanisms, including tunneling and incoherent hopping, through guest molecule interactions.
Main Results:
- Comprehensive modulation of CT dynamics achieved through molecular recognition.
- Charge separation rates accelerated 5.9- to 230-fold, shifting from superexchange to incoherent charge shift.
- Charge recombination rates decreased 1.3- to 2.8-fold in superexchange systems.
- Successful demonstration of guest-induced charge trapping.
Conclusions:
- Molecular recognition provides a facile and reversible strategy for manipulating CT dynamics.
- This noncovalent approach offers superior control over CT compared to traditional methods.
- Opens new avenues for designing efficient artificial light-harvesting and solar energy conversion materials.
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