Long-Range Charge Transport via Redox Ligands in Quantum Dot Assemblies
Yan B Vogel1, Maarten Stam1, Jence T Mulder1
1Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZDelft, The Netherlands.
ACS Nano
|December 14, 2022
Summary
We engineered long-range charge transport in colloidal quantum dot films using redox ligands for efficient carrier transfer. This strategy enables active control over charge mobility in quantum dot assemblies.
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Charge transport in colloidal quantum dot (CQD) assemblies is crucial for electronic devices.
- Traditional methods use inactive spacers, limiting charge mobility by relying on tunneling barriers.
- Developing active strategies for efficient charge transport is essential for advancing CQD-based technologies.
Purpose of the Study:
- To present a novel strategy for actively engineering long-range charge transport in CQD assemblies.
- To move beyond inactive spacers and introduce functionalities that facilitate carrier transfer.
- To understand and control charge transport mechanisms within CQD/redox ligand systems.
Main Methods:
- Utilizing electronically coupled redox ligands to introduce active electronic states within CQD assemblies.
- Employing a self-exchange chain reaction mechanism for interparticle carrier transfer.
- Investigating charge transport modes, their energetic positions, and kinetics.
- Modulating Fermi level and redox ligand coverage to manipulate charge transport.
Main Results:
- Demonstrated active engineering of long-range charge transport in CQD assemblies.
- Established a pathway for carrier transfer via redox ligand functionalities, bypassing passive tunneling barriers.
- Identified distinct charge transport modes and their associated energetics and kinetics.
- Showcased rational control over charge transport through Fermi level and ligand coverage adjustments.
Conclusions:
- Redox ligands offer an effective strategy for active control of charge transport in CQD films.
- This approach enables efficient, long-range carrier transfer, surpassing limitations of inactive spacers.
- Understanding and manipulating charge transport mechanisms is key to optimizing CQD-based electronic applications.
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