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

ABSTRACT 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.