Flexoelectric effect on electric potential in piezoelectric graphene-based composite nanowire: Analytical and numerical modelling

Abstract

In this work, an analytical model was developed to study the distribution of electric potential in a graphene reinforced nanocomposite (GRNC) nanowire. The electromechanical responses such as electric potential and deflection of cylindrical GRNC cantilevered nanowire were investigated. Moreover, the conservative fully coupled finite element (FE) models were developed to validate the analytical predictions. Analytical solution shows that the piezoelectric potential in the GRNC nanowire depends on the transverse force, but it is not a function of the force acting along its axial direction. The electric potential in the tensile and compressive sections of nanowire is antisymmetric along its cross-section, making it as a “parallel plate capacitor” for nanopiezotronics applications such as nanogenerator and piezoelectric field effect transistor due to potential drop across the nanowire which assists as the gate voltage. The predictions of potential distributions across the GRNC nanowire considering piezoelectricity show better agreement with FE predictions. Outcomes of the current work reveal that the flexoelectric effect on the electromechanical behavior of GRNC nanowire is noteworthy and cannot be ignored. © 2020 Elsevier Masson SAS