With the onset of the 5G era, wearable flexible electronic devices have developed rapidly and gradually entered the daily life of people. However, the vast majority of research focuses on the integration of functions and performance improvement, while ignoring electromagnetic hazards caused by devices. Herein, the 3D double conductive networks are constructed through a repetitive vacuum-assisted dip-coating technique to decorate the 2D MXene and 1D silver nanowires on the melamine foam. Benefiting from the unique porous structure and multi-scale interconnected frame, the resultant composite foam exhibited high electrical conductivity, low density, superb electromagnetic interference shielding (48.32 dB), and Joule heating performance (up to 90.8 °C under 0.8 V). Furthermore, a single-electrode triboelectric nanogenerator (TENG) with powerful energy harvesting capability is assembled by combining the composite foam with an ultra-thin Ecoflex film and a polyvinylidene fluoride film. Simultaneously, the foam-based TENG can also be considered a reliable wearable sensor for monitoring activity patterns in different parts of the human body. The versatility and scalable manufacturing of high-performance composite foams will provide new design ideas for the development of next-generation flexible wearable devices.
Hydrogel has great application prospect in the field of flexible wearable devices; however, its poor antifreezing and antidrying properties hinder its applications in wearable devices. Herein, a self-adhesive glycerol-hydrogel (G-hydrogel) with antifreezing and antidrying properties was prepared successfully. The glycerol and water double-solvent system endowed excellent antifreezing and antidrying properties with hydrogel, which ensured the flexibility of the G-hydrogel even after being frozen for 24 h at −15 °C or stored at room temperature for a long time. Polydopamine (PDA)-intercalated bentonite (BT) incorporated into the G-hydrogel contributed good comprehensive mechanical property to the G-hydrogel. The peeling test results confirmed that G-hydrogel has good adhesion to natural and synthetic materials because of the existence of PDA with catechol structure. Particularly, the G-hydrogel presented marvelous sensing capabilities for strain and pressure and could monitor the movements of a human. In summary, this kind of self-adhesive, antidrying, and antifreezing hybrid G-hydrogel may be a very promising soft material for flexible wearable devices.
危险品化学品经营许可证（带存储）