The conversion of ecofriendly waste energy into useable electrical energy is of significant interest for energy harvesting technologies. Piezoelectric nanogenerators based on organic/inorganic hybrid materials are a key promising technology for harvesting mechanical energy due to their high piezoelectric coefficient and good mechanical flexibility. However, the negative piezoelectric effect of the polymer component in composite devices severely undermines its overall piezoelectricity, compromising the output performance of PVDF-based piezoelectric hybrid nanogenerators. Here, to conquer this, we report a two-step poling schedule to orient the dipoles of organic and inorganic components in the same direction. The optimized nanogenerator delivers a combination of high piezoelectric coefficient, great output performance, and remarkable stability. The isotropic piezoelectricity in the composite device collaborates to output a maximum voltage of 110 V and a power density of 7.8 μW cm-2. This strategy is also applied to elevate the piezoelectricity of other organic/inorganic-hybrid-based nanogenerators, substantiating its universal applicability for composite piezoelectric nanogenerators. This study presents a feasible strategy for enhancing the effective output capability of composite nanogenerator technologies.
Keywords: composite film; energy harvesting; negative piezoelectricity; piezoelectric nanogenerator; polarizing.