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Updated: Jun 27, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Tuning Electronic Structure and Piezoresistivity of Graphene by Monovacancy Defect Concentration: A First-Principles
Shengsheng Wei1,2,3, Shuaituan Wang1,2,4, Ningning Su1,2,3
1Shanxi Key Laboratory of Graphene Sensing Materials and Devices, North University of China, Taiyuan 030051, China.
Molecules (Basel, Switzerland)
|June 26, 2026
Summary
Monovacancy defects in graphene significantly enhance piezoresistive sensor performance by altering electronic structure and increasing the gauge factor. This defect engineering offers a pathway for developing advanced graphene-based sensors.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene possesses excellent mechanical and electrical properties, making it suitable for piezoresistive sensors.
- Lattice defects in graphene can negatively impact device performance by altering its electronic structure.
Purpose of the Study:
- To investigate the impact of monovacancy defect concentrations (2%-8%) on graphene's structure, electronic properties, and piezoresistive performance.
- To understand the microscopic mechanisms behind defect-induced electronic modulation in graphene.
Main Methods:
- First-principles calculations were employed to simulate and analyze defective graphene structures.
- Systematic investigation of geometric, electronic, and piezoresistive properties at varying defect concentrations.
Main Results:
- Monovacancy defects cause lattice distortions and form non-hexagonal rings (5-9 structures) at higher concentrations.
- Defects induce a tunable band gap, with a maximum of 0.697 eV at 6% concentration, and create localized, p-type states.
- The gauge factor of graphene is significantly enhanced, reaching 118.23 (36x pristine graphene) at 6% defect concentration.
Conclusions:
- Monovacancy defects critically influence graphene's electronic structure and piezoresistive behavior.
- Defect engineering in graphene is a viable strategy for designing high-performance piezoresistive sensors.
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