One-Step Coaxial Electrospinning of PS/BTO@PVDF Core–Shell Nanofibers for Double-Layered TENGs with Ferroelectric-Enhanced Charge Storage Layer

The growing demand for sustainable and efficient energy solutions for portable and wearable electronics has resulted in significant advancements in the field of triboelectric nanogenerators (TENGs). Although numerous studies have presented novel methods to enhance the TENG performance by incorporating functional intermediate layers, complex multistep fabrication processes pose challenges for practical applications. In this study, polystyrene (PS)/BaTiO₃ (BTO)@polyvinylidene fluoride (PVDF) core–shell nanofibers (NFs) were developed through a one-step coaxial electrospinning process, simplifying fabrication while significantly increasing the energy conversion efficiency of the TENG. The PS core functioned as a charge storage layer, increasing the peak-to-peak voltage (V_pp) from 75.4 to 195.7 V by providing additional electron-trapping sites. Incorporating BTO nanoparticles (NPs) within the PS core further increased the surface charge density and reduced charge recombination through the residual dielectric polarization of the BTO NPs. This resulted in a maximum V_pp of 292 V at a BTO concentration of 30 wt %. Systematic investigations revealed that the surface potential of the NFs decreased considerably upon incorporating an appropriate amount of BTO NPs, owing to the modulated dielectric and ferroelectric properties of the NFs. This innovative approach achieved a substantial improvement in TENG performance while reducing the fabrication complexity, demonstrating its potential for sustainable energy-harvesting applications.