High-Performance\nFlexible Pressure Sensor with Micropyramid\nStructure for Human Motion Signal Detection and Electromagnetic Interference\nShielding

Flexible pressure sensors have a wide range of applications\nin\nthe field of human motion signal detection, but the electromagnetic\nradiation generated during the monitoring process has become an unavoidable\nproblem. Nowadays, it is still a challenge to develop high-performance\npressure sensors with excellent electromagnetic interference (EMI)\nshielding performance. Herein, the Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> MXene/carbon fiber/multiwalled carbon nanotube/polydimethyl­siloxane\n(MXene/CMP) films with a micropyramidal structure were developed by\nthe technology of vacuum high-temperature hot pressing and spray deposition.\nBenefiting from the dielectric loss of the conductive fillers and\nthe presence of the microstructure, the MXene/CMP film exhibits excellent\nEMI shielding performance, and the EMI shielding efficiency (SE) can\nreach 49.37 dB. Besides, the introduction of CF effectively improves\nthe mechanical properties of the MXene/CMP films, and the MXene nanosheets\ndeposited on the surface of the film can reduce stress concentration,\nwhich in turn delays the expansion of cracks. Furthermore, the MXene/CMP\nsensor exhibits high sensitivity (89.76 kPa<sup>–1</sup>) and\nfast response/recovery time (61/60 ms). The deformation of microstructure\nand the construction of conductive networks enable the sensor to realize\nthe monitoring of human motion signals (such as finger bending, knee\nbending, wrist bending, etc.). Meanwhile, the sensor maintains sensing\nstability even after 2000 pressure cycles, which can be attributed\nto the improvement in mechanical properties. In summary, the developed\nhigh-performance flexible pressure sensor with micropyramid structure\nhas great application prospects in wearable devices and healthcare.