Nonlinear electrical output enhancement via compositional matching in ZnO nanorod-PVDF/CB-PDMS hybrid...

An integrated piezoelectric-triboelectric hybrid nanogenerator is developed through vertical integration of electrospun zinc oxide (ZnO) nanorod-embedded poly(vinylidene fluoride) (PVDF) nanofibers and a microstructured carbon black/polydimethylsiloxane (CB/PDMS) composite layer. The incorporation of one-dimensional ZnO nanorods promotes the formation of the electroactive β-phase in PVDF nanofibers, enhancing strain-induced polarization under mechanical deformation. Meanwhile, the microstructured CB/PDMS layer facilitates regulated charge transport and stabilized electrostatic conditions during contact-separation cycles through optimized CB percolation. Systematic compositional tuning of ZnO nanorod content and CB loading establishes clear correlations among the β-phase fraction, relative permittivity, peak-to-peak output voltage, and peak power density. The optimized device achieves 37.28 V and a peak power density of 34.75 μW cm^-2, significantly exceeding individual piezoelectric and triboelectric outputs. A hybrid coupling enhancement factor is introduced to quantify nonlinear voltage amplification beyond linear superposition, revealing synergistic performance enabled by compositional matching; the observed 3.65-fold enhancement in peak power density relative to the sum of individual contributions further corroborates the nonlinear electrodynamic coupling. The enhanced response is interpreted within a displacement-current framework derived from the Maxwell-Ampère law, demonstrating field-mediated coupling between triboelectric and piezoelectric mechanisms. This work establishes a rational materials design strategy for synergistic performance enhancement in flexible hybrid nanogenerators for mechanical energy harvesting and self-powered sensing applications.