Flexible capacitive pressure sensors with simple structure and low power consumption have attracted great interest because of their promising applications in wearable electronics. However, assembling a pressure sensor with high sensitivity, low detection limit, and wide dynamic range is still a big challenge. Here, a sandwich‐like, flexible capacitive pressure sensor is reported with micropyramid array electrode and porous dielectric layer. Under external stimulus pressure, the distance between two electrodes, and dielectric constant of dielectric layer will change simultaneously, resulting in high sensitivity (2.51 kPa−1) of the sensor. Due to the micropyramid array electrode, the sensor exhibits low detection limit (2.0 Pa), fast response speed (84 ms), wide working range (>10 kPa), and high stability (>5000 dynamic cycles). Finite‐element analysis also reveals that the larger duty ratio and altitude of micropyramid arrays lead to higher sensor sensitivity. By depicting the deformation of micropyramid during compression, the sensing mechanism of these sensors is discovered, providing a potential direction for developing sensitivity and linear range. Additionally, the sensor has been demonstrated to be efficient in monitoring human motion, such as muscle activation and rope skipping, showing high potential in the field of sport wearable equipment.

Lightweight, flexibility, and low thickness are urgent requirements for next-generation high-performance electromagnetic interference (EMI) shielding materials for catering to the demand for smart and wearable electronic devices. Although several efforts have focused on constructing porous and flexible conductive films or aerogels, few studies have achieved a balance in terms of density, thickness, flexibility, and EMI shielding effectiveness (SE). Herein, an ultrathin, lightweight, and flexible carbon nanotube (CNT) buckypaper enhanced using MXenes (Ti3C2Tx) for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process. The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100 μm. The hybrid buckypaper with an MXene content of 49.4 wt% exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15 μm, which is 105% higher than that of pristine CNT buckypaper. Furthermore, an average specific SE value of 5.7 × 104 dB cm2 g−1 is exhibited in the 5-μm hybrid buckypaper. Thus, this assembly process proves promising for the construction of ultrathin, flexible, and high-performance EMI shielding films for application in electronic devices and wireless communications.

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Metal−organic frameworks (MOFs) are booming as a promising precursor for constructing lightweight, highefficiency microwave absorbing (MA) material. However, it is still a challenge to rationally design three-dimensional (3D), porous MOF-derived MA materials with a stable structure and strong and wideband MA performance. Herein, a 3D hybrid nanostructure (CNT/FeCoNi@C) comprising MOF-derived magnetic nanospheres and Fe-filled carbon nanotube (CNT) sponge has been controllably fabricated to enhance the absorption ability and broaden the effective absorption bandwidth (EAB). The magnetic nanospheres are uniformly anchored on the CNT skeleton, forming hybrid network structures, which enhance interface polarization, electron transportation, and impedance matching. The minimum reflection loss (RL) and EAB of the asprepared CNT/FeCoNi@C sponges reach −51.7 dB and 6.0 GHz, respectively, outperforming most reported MOF-based wave absorbers. This work provides not only a novel design of MOF-derived 3D nanostructures but also an effective guide for the optimization of electromagnetic properties and absorbing performance in MA material.