Nacre-Mimetic Electronic Skin Based on Multilayered Ti3C2Tx/Carbon Nanotubes/Thermoplastic Polyurethane Fibrous Mat with Self-Powered Ability for Postural Correction Training
Flexible wearable electronics demand multifunctional e-skins that reconcile high strain sensitivity, wide operating range, low detection limit, air permeability, and self-powered capability. Existing MXene-based sensors suffer from rapid conductive network destruction due to weak inter-sheet interactions, limiting their working range. Inspired by the brick-and-mortar microstructure of natural nacre, a multilayered Ti3C2Tx (MXene)/carbon nanotubes (CNTs)/thermoplastic polyurethane (TPU) fibrous mat was fabricated via electrospinning and spraying. The tunable multilayer architecture yields a gauge factor of 5.8 × 10^4, a sensing range up to 535% strain, a detection limit of 0.15% strain, an 80 ms response time, and good durability. The sensing mechanism relies on the synergistic evolution of a 2D MXene/1D CNT conductive network and synchronous microcrack expansion. The e-skin also functions as a single-electrode triboelectric nanogenerator (TENG) with high output and stability, enabling tactile sensing and powering LEDs. Demonstrations include human physiological signal acquisition, cardiopulmonary resuscitation (CPR) training via smart gloves, and posture correction training for athletes. This nacre-mimetic self-powered e-skin offers a viable route for ergonomics, emergency medical services, and athlete training assessment.