Piezoelectric nanosensors were prepared with a novel type of dehydrofluorinated poly(vinylidene fluoride) (PVDF) nanofibrous membrane. With the synergistic effect of the dehydrofluorination reaction and applied high voltage electric field, the piezoelectric and energy storage properties of fibrous membranes attained great improvement. It was found that the simultaneous introduction of conjugated double bonds to the backbone of PVDF which was accompanied with the elimination of HF, resulted in the decrease of its molecular weight, solution viscosity and hydrophobicity. The crystalline phase, diameter, piezoelectric and energy storage properties of electro-spun PVDF nanofiber membranes significantly depend on the degree of HF elimination in dehydrofluorinated PVDF. The dehydrofluorinated PVDF with 5 hours of reaction exhibits the highest discharged energy density (W_rec) and energy storage efficiency (η), but excessive dehydrofluorination reaction is unfavorable to the energy storage properties. In addition, the dehydrofluorinated PVDF fiber membrane-based nanosensor possesses a larger electrical throughput (open circuit voltage of 30 V, which is three time that of the untreated PVDF), indicating that the introduction of double bonds can also improve the piezoelectric properties of PVDF nanofibers.

Intelligent electronic textiles have important application value in the field of wearable electronics due to their unique structure, flexibility, and breathability. However, the currently reported electronic textiles are still challenged by issues such as their biocompatibility, photothermal conversion, and electromagnetic wave contamination. Herein, a multifunctional biomass-based conductive coating was developed using natural carboxymethyl starch (CMS), dopamine and polypyrrole (PPy) and then further employed for constructing multifunctional intelligent electronic textiles. The prepared textiles had excellent water resistance, breathability, antioxidant and antibacterial activities, electromagnetic shielding (33 dB) as well as photothermal conversion performance, and stability. Notably, the fabricated textile could be heated from room temperature to 55 °C within 10 s under infrared radiation, and then the surface temperature of the textile could be reduced to 40 °C (τ_s = 42.05 s) within 20 s, holding great significance for research on new wearable photothermal textiles. Furthermore, the textile was utilized as a skin strain sensor, demonstrating high sensitivity to temperature, strain, photothermal and bioelectric signals and motion detection. It could monitor the physiological signal, motion control, and body temperature change of the human body in real time, offering significant potential to be applicable to integrated wearable intelligent textiles and skin bioelectronics.