Multiscale Structure-Function Coupling in High-Filler PZT/SMPU Nanofiber Yarns for Wearable Energy Systems

Flexible energy harvesters for wearable electronics must conform to complex body surfaces while maintaining high output and mechanical durability. However, existing nanofiber-based piezoelectric systems often suffer from poor structural integration and limited electromechanical coupling. Here, we construct PZT/SMPU nanofiber yarns via conjugate electrospinning and integrate them into programmable woven fabrics with plain, twill, and satin structures. Under 50 Hz, 0.8 mm vibration, satin fabrics woven from PZT > 30 yarns achieved an output of 343.34 mV and 411.08 pA, outperforming plain weave counterparts by over 18.39%. Finite element analysis (FEA) revealed 36.36% higher surface stress in satin structures, while shape-memory-assisted pre-deformation further enhanced curved-surface performance by 104.94%. The devices retained over 95% of initial voltage after 31 600 cycles. This study demonstrates the synergistic enhancement from nanofiber alignment and low-interlacing weave design, establishing a scalable strategy for high-sensitivity, conformal, and durable energy-harvesting textiles.