Nanogenerators facilitated piezoelectric and flexoelectric characterizations for bioinspired energy harvesting materials

Abstract Deformation-derived electric polarization has been adopted as a core technology for electromechanics devices. Now, as the device experiences the multiple degrees of deformation, such as compressing, bending and stretching, upon the development of technology, the characterization techniques for devices need to be retrofitted to account for the different mechanistic origins of electric polarization. Here, we report the nanogenerators that enable a facile characterization of piezoelectricity and flexoelectricity in the device scale. The quadrant electrode NG along with nematically organized M13 bacteriophage provides the comprehensive piezoelectric coefficients while the flexoelectric coefficient was extracted from sandwich electrode NG. This approach offers a perspective on how to separate the piezoelectric and flexoelectric effects from the electric outputs. Such characterization will not only allow us an understanding of fundamental flexoelectric mechanisms but also help us to establish design rules for flexible electromechanical devices.