All‐in‐One Wrinkled Phase‐Change Fibers for Synchronous Stretchable Thermal Management and Electromagnetic Interference Shielding

ABSTRACT Developing multifunctional textiles integrating energy‐efficient thermal management and robust electromagnetic interference (EMI) shielding remains a significant challenge. Herein, a stretchable phase‐change fiber membrane with a programmable wrinkled conductive network is fabricated by in situ depositing silver nanoparticles (AgNPs) on a pre‐stretched coaxial electrospun substrate. Its hierarchical structure, comprising paraffin wax (PW) encapsulated in the polyurethane (PU) shell and a surface‐wrinkled AgNP layer, delivers a high latent heat of 73.8 J g ⁻¹ , along with deformable photothermal and Joule heating. Numerical simulations corroborate that the synergy of dual‐mode heating and PW‐based energy storage allows effective personal thermal management at low temperatures. Moreover, the membrane exhibits an initial EMI shielding effectiveness (SE) of 66.4 dB, retaining 33.71 dB even at 100% strain due to its elastic wrinkled topology. Endowed with hydrophobicity, breathability, and mechanical stretchability, the composite presents a promising platform for next‐generation wearable devices requiring integrated thermal regulation and adaptive EMI protection.