Electromechanical coupling in piezoelectric nanoplate due to the flexoelectric effect.

Flexoelectricity, referring to the electrical polarization generated by strain gradients, is an electromechanical coupling phenomenon in all dielectric materials. Based on the Kirchhoff plate theory, this paper investigates the influence of flexoelectricity on the electromechanical coupling response of piezoelectric circular nanoplates with different electric boundary conditions. Using the variational principle and Gibbs free energy, the governing equations and boundary conditions of piezoelectric nanoplates are derived. The analytical solutions of the deflection, polarization, and induced electric potential are obtained. The results show that the flexoelectric effect is size-dependent and has a more significant influence on the electrostatic responses than the piezoelectric effect at the nanoscale. The results also show that the induced electric potential due to the flexoelectric effect may be helpful for sensing or energy harvesting designs. [ABSTRACT FROM AUTHOR]