Engineering piezoelectric efficiency in phase-separated PVDF nanocomposites using In2O3-ZnO heterostructure

Abstract The current research explores the piezoelectric output voltage efficiency of polyvinylidene fluoride (PVDF) nanocomposites containing In 2 O 3 -ZnO (IZO) heterostructures fabricated via phase separation methodology. Non-solvent induced phase separation using octanol creates uniform pores and spherulites within the polymer composites. Heterostructures of nanomaterials, where ZnO forms a quasi-spherical interface with In 2 O 3 crystalline nuclei, enhance the number of crystallites with reduced size, thereby contributing to the piezoelectric performance. Phase separation results in granular and rough surface morphology of the PVDF spherulites, advancing the β-phase, which is the primary reason for power generation. A specific circular sample of 2% PVDF/IZO with a diameter of 3 cm and thickness of ~ 150 µm produced the highest output voltage of 1.32 V, almost 26 times higher than that of the neat PVDF film of the same dimensions. The study highlights the application of phase separation as a cost-effective, self-polarization strategy to significantly increase the phase content, thereby supporting sustainable energy harvesting.