Simulation of Graphene Piezoresistivity Based on Density Functional Calculations

Abstract

The piezoresistive effect in graphene ribbon has been simulated based on the first-principles electronic-state calculation for the development of novel piezoresistive materials with special performances such as high flexibility and low fabriccation cost. We modified theoretical approach for piezoresistivity simulation from our original method for semiconductor systems to improved procedure applicable to conductor systems. The variations of carrier conductivity due to strain along with the graphene ribbon models (armchair model and zigzag model) have been calculated using band carrier densities and their corresponding effective masses derived from the one-dimensional electronic band diagram. We found that the armchair-type graphene nano-ribbon models have low conductivity with heavy effective mass. This is a totally different conductivity from two-dimensional graphene sheet. The variation of band energy diagrams of the zigzag-type graphene nano-ribbon models due to strain is much more sensitive than that of the armchair models. As a result, the longitudinal and transverse gauge factors are high in our calculation, and in particular, the zigzag-type graphene ribbon has an enormous potential material with high piezoresistivity. So, it will be one of the most important candidates that can be used as a high-performance piezoresistive material for fabricating a new high sensitive strain gauge sensor.

Graphene-Based Strain Gauge on a Flexible Substrate

“…From our calculations, the LRGO/PET strain gauge was found to have a gauge factor of 61.5, which is far higher than those of commercial metal-alloy-based strain gauges and consistent with the simulation results obtained by Gamil et al, (29) but less than those of strain gauges based on single-layer graphene films fabricated using complex and expensive high-vacuum CVD methods. (3) This highlights the practicality of the proposed method, which can be used to easily fabricate strain gauge sensors that are much more sensitive than commercial metallic strain gauges and more feasible than silicon single-crystal strain gauges fabricated using expensive microfabrication techniques.…”

Piezoresistive Effect in Plasma-Doping of Graphene Sheet for High-Performance Flexible Pressure Sensing Application

“…First, with quantum size effects, it is possible to modulate the bandgap gap by tweaking the width and specific edge of the strained graphene (e.g., zigzag-type or armchair-type graphene nanoribbons). 10,11 Second, it is also possible for the symmetry breaking of the graphene lattice to open the band gap (such as through the interaction between the graphene and silicon carbide substrate or by the application of an external electronic field on bilayer graphene). 12,13 Third, boron (B) or nitrogen (N) doping could be used for the graphene layer, which is also capable of opening the band gap of graphene.…”

“…However, several mechanisms for engineering the band gap of graphene have been reported, which can be classified into three aspects. First, with quantum size effects, it is possible to modulate the bandgap gap by tweaking the width and specific edge of the strained graphene (e.g., zigzag-type or armchair-type graphene nanoribbons). , Second, it is also possible for the symmetry breaking of the graphene lattice to open the band gap (such as through the interaction between the graphene and silicon carbide substrate or by the application of an external electronic field on bilayer graphene). , Third, boron (B) or nitrogen (N) doping could be used for the graphene layer, which is also capable of opening the band gap of graphene. − However, with the difficulty of specifically controlling the edge of graphene, the complexity of electrically gated bilayer graphene, and the specific substrate of graphene placement, the doping technique is considered to possibly be the simplest, most versatile, and cost-effective method for the modulation of the band gap at the K (K′) point in the graphene electronic structure for a flexible pressure sensor application. In addition, to the best of our knowledge, the use of the piezoresistive effect of graphene through the doping process for a flexible pressure sensor application has not yet been reported.…”

Fabricating a highly sensitive graphene nanoplatelets resistance-based temperature sensor

“…GNPs are stacks of multigraphene layers in a two-dimensional nano particulate format (basal planes of carbon atoms packed into a hexagonal array) having a platelet shape that are identical to those found in the walls of carbon nanotubes, but in a planar form. The unique size and platelet morphology of GNPs makes it effective at providing barrier properties, while its pure graphitic composition makes it as excellent electrical and thermal conductors (Kuan et al , 2018; Gamil et al , 2014b; Gamil et al , 2012; Gamil et al , 2013). As a result, GNPs are considered a game changer for numerous sensing application.…”