Biomimetic Pyrolytic MXene‐Based Multifunctional Films with Multi‐Level Structure for Wearable Piezoresistive Devices and Bioelectronics

Abstract MXene films possess excellent controllable electrical conductivity, mechanical and chemical characteristics, showing great potential in the construction of new‐generation flexible wearable devices. However, achieving multifunctional applications of MXene through simple and scalable methods is a major challenge. Inspired by skin tissue, a pyrolysis‐MXene flexible film (P‐MX) with randomly microspine‐like and internal hollow coupled structure is prepared through the combination of interface‐induced self‐assembly, solution thermal deposition, and high‐temperature pyrolysis methods. The multi‐level structure provides more variable conductive paths during compression and ensures structural integrity under high pressure. The synergistic treatment of oxygen plasma and polyvinyl alcohol (PVA) enhances adhesion strength highest up to 46.87 times compared to a single surface treatment strategy between P‐MX sensitive components and flexible substrate. Such P‐MX sensor demonstrates an extremely high sensitivity (76.79 kPa⁻¹ within 0–25.39 kPa), a wide detection range (up to 1275.19 kPa), fast response/ recovery time (22 ms/32 ms), and high cycle reliability (over 18 000 cycles). It can also perceive weak signals (12 mg/4.8 Pa). Additionally, P‐MX exhibits a significant increment in specific capacitance. It exhibits excellent prospects in human‐machine interaction, neural electrodes, and motion detection. These findings open new pathways for the practical application of MXene‐based wearable piezoresistive devices and bioelectronics.