Graphene-Based Ultrasensitive Strain Sensors

Abstract

We\nperformed density function theory calculations to study the\neffect of strain on electronic properties of pristine and doped graphene.\nA dramatic change in density of states (DOS) and band structure is\nobserved on doped graphene in the presence of uniaxial and biaxial\nstrain. The analyses of density of states variations at the Fermi\nlevel and band gap in the presence of strain provide insight into\nthe role of strain in affecting the conductivity of graphene. We demonstrated\nthat band gap can be widely modulated in the presence of uniaxial\nand biaxial strains. It is found that the presence of dopants at low\nconcentration can enhance the sensitivity of the sensor making it\nan ultrasensitive high-performance sensor which can sense strain up\nto ∼0.0001 at low doping concentration, which is almost impossible\nfor currently used sensors, thus transforming graphene into an efficient\nstrain sensing material. Due to its outstanding performance, the strain\nsensor can satisfy the need for subtle, complex, and large human motion\nmonitoring that indicates its potential for its great applications\nin real-time motion monitoring, mechanical control, and health monitoring.\nThese results can enhance our understanding of strain effects on electric\nproperties of graphene and other two-dimensional (2D) materials.