Diversity of transverse flexoelectricity in non-poled polyvinylidene fluoride

As a promising electromechanical effect in dielectric materials, flexoelectricity describes the linear relation between a strain gradient and its induced electric polarization. Flexoelectricity in polymeric materials is separated from that of crystal dielectrics in both the mechanism and value due to their complicated structures. Independent works reported flexoelectric coefficients of one material as different values, even spanning magnitudes. Curiosity then comes on the exact flexoelectric coefficients of polymeric dielectrics. In this work, diversity of transverse flexoelectricity in non-poled bulk polyvinylidene fluoride on three geometric dimensionalities is researched and discussed. An obvious diversity of transverse flexoelectricity is revealed by investigating two transverse flexoelectric coefficient components, which may be induced by pre-existed charges of materials. This work indicates that the flexoelectric response exists in a range in one polymeric material. This result also expands a possibility of applications with flexoelectricity in polymeric materials and additionally highlights the importance of the mechanism in low-symmetric dielectric solid materials.