Effect of Flexoelectricity on the Electromechanical Coupling of Piezoelectric Nanoplates

Flexoelectricity is referred as an instantaneous polarization of dielectrics in response to non-uniform strains or strain gradients. Due to the fact that strain gradients are inversely proportional to the feature size of structures, the flexoelectricity is believed to be significant at the nano-scale. Based on the extended linear piezoelectricity theory, this work attempts to investigate the flexoelectric effect upon the electromechanical coupling of a piezoelectric nanoplate by developing a modified Kirchhoff plate model. Simulation results on the electroelastic fields indicate that the flexoelectric effect is size-dependent, which is more prominent for thinner plates with smaller thickness. It is also observed that the effect of the flexoelectricity upon the electromechanical coupling of the piezoelectric nanoplate is sensitive to the applied electric voltage. This study aims to establish a further understanding of the flexoelectric effect on the electromechanical coupling of piezoelectric nanomaterials, thus provide guidance for the design and applications of piezoelectric nanostructures.