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Atomically well-defined nitrogen doping for cross-plane transport through graphene heterojunctions
Hewei Zhang1, Ping Zhou2, Abdalghani Daaoub3
1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Pen-Tung Sah Institute of Micro-Nano Science and Technology, IKKEM, Xiamen University 361005 Xiamen China yangyang@xmu.edu.cn whong@xmu.edu.cn.
Chemical Science
|June 9, 2023
Summary
Nitrogen doping graphene creates tunable bandgaps for electronics. This study reveals how nitrogen atom placement and quantity significantly alter charge transport in graphene heterojunctions at the atomic level.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Nitrogen doping graphene forms heterojunctions with tunable bandgaps.
- Applications include electronics, electrochemistry, and sensing.
- Microscopic properties of atomic-level nitrogen-doped graphene remain unclear due to diverse doping sites.
Purpose of the Study:
- Investigate cross-plane charge transport in atomically defined nitrogen-doped graphene heterojunctions.
- Elucidate the impact of nitrogen doping on electronic properties.
- Understand the role of doping site and number on conductance.
Main Methods:
- Fabrication of atomically well-defined nitrogen-doped graphene heterojunctions.
- Measurement of cross-plane charge transport.
- Combined ultraviolet photoelectron spectroscopy and theoretical calculations.
Main Results:
- Conductance varied by up to ~288% with different nitrogen doping numbers.
- Conductance varied by ~170% with nitrogen doping at different positions.
- Nitrogen insertion stabilized frontier molecular orbitals, altering HOMO/LUMO relative to electrode Fermi level.
Conclusions:
- Nitrogen doping significantly impacts charge transport in graphene heterojunctions.
- Atomic-level understanding of doping effects is crucial for material design.
- Provides insights into tailoring electronic properties via controlled nitrogen incorporation.
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