Wearable electronics with healability have been extensively researched recently. To provide wearing comfort, fabrics are often adopted as the base materials. Intrinsic healability, however, is challenging for fabrics because of the inability to retain the fibrous morphologies. Herein, an unprecedented strategy is presented for producing electrospun fabrics that are intrinsically healable by carefully balancing the crystalline structural support and healing ability. Fluorocarbon polymers with different crystallinities are mixed with ionic liquids to form ionogels, which are spun into fabrics using a unique wet electrospinning apparatus. Importantly, the introduction of the crystalline domains prevents the fusion of the electrospun fibers; even after 1 year, no significant morphological change is observed. The nonwoven fabrics are not only stretchable and waterproof but also intrinsically healable. The ion–dipole interactions between the polar copolymers and ionic liquids provide the reversible physical crosslinking essential to the healing capability. When damaged, the fabrics can be overlapped and healed after applying pressure. Moreover, the fabrics demonstrate healability underwater. Healable sensing devices, pressure, and tensile sensors are also designed by printing ion‐conductive gels as electrodes. Both devices show good stability before and after healing. This work demonstrates the first example of intrinsically healable electrospun fabrics, which are promising for fabric‐based wearable electronics and smart clothing.

Surface-enhanced Raman scattering (SERS) has been a useful sensing technique, in which inelastic light scattering can be significantly enhanced by absorbing molecules onto rough metal surfaces or nanoparticles. Although many methods have been developed to prepare SERS substrates, it is still highly desirable and challenging to design SERS substrates, especially with highly ordered and controlled three-dimensional (3D) structures. In this work, we develop novel SERS substrates with regular volcano-shaped polymer structures using the versatile solvent on-film annealing method. Polystyrene (PS) nanospheres are first synthesized by surfactant-free emulsion polymerization and assembled on poly(methyl methacrylate) (PMMA) films. After annealing in acetic acid vapors, PMMA chains are selectively swollen and wet the surfaces of the PS nanospheres. By selectively removing the PS nanospheres using cyclohexane, volcano-shaped PMMA films can be obtained. Compared with flat PMMA films with water contact angles of ∼74°, volcano-shaped PMMA films exhibit higher water contact angles of ∼110°due to the sharp features and rough surfaces. The volcano-shaped PMMA films are then coated with gold nanoparticles (AuNPs) as SERS substrates. Using rhodamine 6G as the probe molecules, the SERS results show that the Raman signals of the volcano-shaped PMMA/AuNP hybrid substrates are much higher than those of the pristine PMMA films and PMMA films with AuNPs. For the volcano-shaped PMMA/ AuNP hybrid substrates using 400 nm PS nanospheres, a high enhancement factor (EF) value of ∼1.12 × 10 5 with a detection limit of 10 −8 M is obtained in a short integration time of 1 s. A linear calibration line with an R 2 value of 0.918 is also established, demonstrating the ability to determine the concentrations of the analytes. This work offers significant insight into developing novel SERS substrates, which is crucial for improving the detection limits of analytes.

Phase changing materials (PCMs) have been widely investigated because of their unique properties and applications. In recent years, PCMs have been embedded into polymer fibers for thermal regulating purposes. The PCMcontaining polymer fibers, however, usually suffer the leakage problem because PCMs are not covered well by polymers in fibers. To solve this problem, in this study, we develop a facile strategy to fabricate PCM-containing polymer fibers without the leakage problem. The PCM/polystyrene (PS) coreshell microspheres are first prepared by suspension polymerization, in which n-hexadecane is used as the PCM. By blending the PCM/PS microspheres into polymethyl methacrylate (PMMA) solutions, The PMMA fibers blended with core-shell PCM/PS microspheres can be prepared via electrospinning. Acetic acid is chosen as the solvent, which can selectively dissolve PMMA and cannot dissolve PS. Therefore, the morphologies of the core-shell PCM/PS microspheres can be maintained during the electrospinning processes. The microspheres and fibers are characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Thermal imaging results demonstrate that the PCM-containing fibers can effectively regulate temperatures and fibers with higher contents of PCM exhibit better thermal regulating behaviors. Repeated thermal regulating experiments are also conducted for up to 4 cycles.