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Abstract 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.

Abstract Flexible and wearable sensing devices have broad application prospects in bio-monitoring such as pulse measurement, motion detection and voice recognition. In recent years, many significant improvements had been made to enhance the sensor’s performance including sensitivity, flexibility and repeatability. However, it is still extremely complicated and difficult to prepare a patterned sensor directly on a flexible substrate. Herein, inspired by typography, a low-cost, environmentally friendly stamping method for the mass production of transparent conductive carbon nanotube (CNT) film is proposed. In this dry transfer strategy, a porous CNT block was used as both the seal and the ink; and Ecoflex film was served as an object substrate. Well-designed CNT patterns can be easily fabricated on the polymer substrate by engraving the target pattern on the CNT seal before the stamping process. Moreover, the CNT film can be directly used to fabricate ultrathin (300 μm) strain sensor. This strain sensor possesses high sensitivity with a gauge factor (GF) up to 9960 at 85% strain, high stretchability (> 200%) and repeatability (> 5000 cycles). It has been used to measure pulse signals and detect joint motion, suggesting promising application prospects in flexible and wearable electronic devices.