Real-life wearable electronics with long-term stable sensing performance are of significant practical interest to public. Wearable pressure sensors with washable, comfortable, breathable, and stable sensing ability are a key requirement to meet the desire. However, effects of ubiquitous ambient moisture and intrinsic defects of current capacitive sensing materials are two factors leading to unstable sensing performance of current pressure sensors. Existing ionic liquid-based materials (i.e., ionic hydrogel, ionic film, or ionic/ elastomers composite) have been used for efficient capacitive pressure sensing but are highly sensitive and especially affected by moisture. In this work, we introduce a washable capacitive pressure-sensing textile based on the use of a hydrophobic poly(ionic liquid) nanofibrous membrane (PILNM) with good mechanical properties and satisfactory moisture proof sensing performance. The PILNM membranes possessing rich ions and microporous structures are novel ideal polymeric dielectric materials for amplification of signals with negligible stimulations. Moreover, the PILNMs exhibit very high stable sensing signals under moisture interference (up to 70% relative humidity) and repeated washings (more than 10 washings), especially suitable for wearable electronics. Notably, the PILNM-based wearable pressure-sensing textiles offer high sensitivity for low pressure and bent chord length changes with a low-pressure detection limit even under harsh deformations. Owing to the superior performance, the PILNM-based wearable pressure-sensing textiles are comfortable to wear and suitable for monitoring different human motions and pulse vibrations at various body positions. Meanwhile, the assembled multiple wearable pressure-sensing array can spatially map the contact area of the pressure stimuli and synchronously reflect finger movements.

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Flexible, ultralight, and mechanically robust electromagnetic interference (EMI) shielding materials are urgently demanded to manage the increasing electromagnetic radiation pollution, but it remains a great challenge to simultaneously achieve ultralight yet mechanically robust properties while retaining high-efficiency EMI shielding performance. Herein, we fabricate a novel waterborne polyurethane/Ti 3 C 2 T x MXene/nickel ferrite (WPU/MXene/NiFe 2 O 4 ) hybrid aerogel by constructing a strong chemical bonding interaction between an NCOterminated WPU prepolymer and hydroxyl functionalized MXene nanosheets. The resultant aerogels exhibit remarkable lightweight and mechanical properties, particularly high compressive stress far exceeding that of other MXene-based and WPU-based porous materials. Furthermore, synergistic effects of the oriented porous architecture and the multiphase skeleton endow the hybrid aerogels with a high Xband EMI shielding effectiveness (SE) of 64.7 dB at a low density of ∼38.2 mg/cm 3 . The corresponding specific SE value achieves 1694−3124 dB•cm 3 /g, and the SSE/d is up to 15,620 dB•cm 2 /g, surpassing that of most reported EMI shielding materials. Importantly, this aerogel, with excellent electromagnetic radiation protection effects and shielding reliability, is highly promising for long-term and effective EMI shielding service in various application environments.

Herein, we develop a novel method to fabricate silver conductive patterns on polyester fabric (PET) by screen printing dopamine (DOPA) tracks first, then reducing silver ions with polydopamine (PDA) tracks, which are self-polymerized from dopamine (DOPA), and finally electroless plating. Polydopamine (PDA) definitely adheres to the surface of the fabric and reduces the silver ions to initiate the electroless plating. This process is confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The conductivity of the well-defined silver patterns on the PET fabric is 0.86 Ω sq. In addition, the electronic patterns fabricated via the proposed method maintains their function under cyclic bending and Scotch®-tape tests, which indicates their great potential for application in flexible devices and wearable electronics.

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