An unexploited property of graphene-based heterojunctions is the tunable doping of the junction via electrostatic gating. This unique property may be key in advancing electronic transport across interfaces with semiconductors. Here, we engineer transport in semiconducting TMDs by constructing a lateral heterostructure with epitaxial graphene and tuning its intrinsic doping to form a
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We study the transport properties of mm-scale CVD graphene p-n junctions, which are formed in a single gated graphene field effect transistor configuration. Here, an electrical-stressing-voltage technique served to modify the electrostatic potential in the SiO2/Si substrate and create the p-n junction. We examine the transport characteristics about the Dirac points that are localized in the perturbed and unperturbed regions in the graphene channel and note the quantitative differences in the Hall effect between the perturbed and unperturbed regions. The results also show that the longitudinal resistance is highly sensitive to the external magnetic field when the Hall bar device operates as a p-n junction.
more » « less- Award ID(s):
- 2210180
- NSF-PAR ID:
- 10524769
- Publisher / Repository:
- Nature Journals
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Nitrogen (N) doping is one of the most effective approaches to tailor the chemical and physical properties of graphene. By the interplay between N dopants and 3D curvature of graphene lattices, N‐doped 3D graphene displays superior performance in electrocatalysis and solar‐energy harvesting for energy and environmental applications. However, the electrical transport properties and the electronic states, which are the key factors to understand the origins of the N‐doping effect in 3D graphene, are still missing. The electronic properties of N‐doped 3D graphene are systematically investigated by an electric‐double‐layer transistor method. It is demonstrated that Urbach‐tail‐like localized states are located around the neutral point of N‐doped 3D graphene with the background metallic transport channels. The dual nature of electronic states, generated by the synergistic effect of N dopants and 3D curvature of graphene, can be the electronic origin of the high electrocatalysis, enhanced molecular adsorption, and light absorption of N‐doped 3D graphene.
