Textile-based triboelectric nanogenerators (T-TENGs), combining the functions of energy harvesting and self-powered sensing with advantages of breathability and flexibility, have received intensive attention, which is vital to the rapid advancements in smart textiles. However, there exists few reports of T-TENGs applied to fires under the intelligent era of high requirements for devices with versatility and multiscenario practicability. Here, in combination with flame-retardant conductive cotton fabric, polytetrafluoroethylene-coated cotton fabric, and a divider, a low-cost and environmentally friendly flame-retardant textile-based triboelectric nanogenerator (FT-TENG) is developed, which is endowed with excellent fire resistance and outstanding energy harvesting capabilities. The cotton fabrics treated with a layer-by-layer self-assembly method show great self-extinguishing performance. Besides, the maximum peak power density of the FT-TENG can reach 343.19 mW/m2 under the tapping frequency of 3 Hz. Furthermore, the FT-TENG still keeps 49.2% of the initial electrical output even after being burned at 17 different positions; 34.48% of the electrical output is also retained when the FT-TENG is exposed to 220 °C. Moreover, the FT-TENGs are successfully applied as energy harvesters for firefighters and self-powered sensors for forest self-rescue and fire alarm systems. This work may provide a promising potential for multifunctional smart textiles in energy harvesting, self-powered sensing, and life or property security.

A porous porphyrin-based hydrogen-bonded organic framework (HOF) was constructed, and its proton conductivity was improved through a two-step guest-tuned strategy. After regulation, the proton conductivity of the HOF reaches 1.59 × 10−1 S cm−1 at 80 °C and 99% RH.

Zwitterionic hydrogels have received great attention due to their excellent nonfouling and biocompatible properties, but they suffer from weak mechanical strength in the saline environments important for biomedical and engineering applications due to the “anti‐polyelectrolyte” effect. Conventional strategies to introduce hydrophobic or non‐zwitterionic components to increase mechanical strength compromise their nonfouling properties. Here, a highly effective strategy is reported to achieve both high mechanical strength and excellent nonfouling properties by constructing a pure zwitterionic triple‐network (ZTN) hydrogel. The strong electrostatic interaction and network entanglement within the triple‐network structure can effectively dissipate energy to toughen the hydrogel and achieve high strength, toughness, and stiffness in saline environments (compressive fracture stress 18.2 ± 1.4 MPa, toughness 1.62 ± 0.03 MJ m–3, and modulus 0.66 ± 0.03 MPa in seawater environments). Moreover, the ZTN hydrogel is shown to strongly resist the attachment of proteins, bacteria, and cells. The results provide a fundamental understanding to guide the design of tough nonfouling zwitterionic hydrogels for a broad range of applications.

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Poly (vinyl alcohol) (PVA) possesses wide applications as food packaging materials, but is difficult to melt process for its strong inter/intra hydrogen bonding. In this work, flexible PVA films with different content of sorbitol plasticizers were prepared by melt processing with the assistance of water. And the influence of sorbitol plasticizer content on the crystallinity, optical transparency, water-retaining capability, mechanical properties, thermal stability and oxygen and water permeability were investigated. The results indicated that sorbitol dramatically improved the melt processing ability of PVA. Sorbitol could interact with PVA to form strong hydrogen bonding interactions, which would decrease the original hydrogen bonding of the matrix, resulting in the decrease of crystallinity degrees. The glass transition, melting and crystallization peak temperatures decreased with the increase of sorbitol. All the films exhibited fine optical transparency. The water retaining capability were improved with the increase of sorbitol. Especially, an increase in elongation at break and decrease in Young's modulus and tensile strength were observed indicating good plasticizing effect of sorbitol on PVA films. In addition, the PVA films prepared in this work exhibited fine barrier properties against oxygen and water, suggesting wide application potential as packaging materials.