Nacre-mimetic electronic skin based on multilayered Ti3C2Tx/carbon nanotubes/thermoplastic polyurethane fibrous mat with self-powered ability for postural correction training

Abstract

With the rapid development of flexible wearable electronic devices, a multifunctional electronic skin with excellent strain sensing performance, satisfactory air permeability, and good self-powered capability for portability is urgently desired. Herein, inspired by the “brick-and-mortar” microstructure of natural nacre, an ultra-stretchable and highly sensitive multifunctional e-skin composed of Ti₃C₂T_x (MXene)/Carbon nanotubes (CNTs)/thermoplastic polyurethane films is developed through electrospinning and spraying technology. Benefiting from the tunable multilayer structural design, the multifunctional e-skin synchronously demonstrates a high sensitivity (gauge factor, GF_max = 5.8 × 10⁴), wide sensing range (up to 535% strain), low detection limit (0.15% strain), fast response time (80 ms) and good durability. The sensing mechanism is developed based on the evolution of a two-dimensional (2D) MXene/1D CNTs synergistic conductive network and the expansion of the microcracked structure synchronously. The multifunctional e-skin is also assembled as a single-electrode triboelectric nanogenerator, which shows high triboelectric output and good stability, broadening the application of the multifunctional e-skin in tactile sensing. The nacre-mimetic self-powered e-skin is demonstrated for human physiological signal acquisition, cardiopulmonary resuscitation (CPR), and posture correction training, presenting fascinating application strategies for ergonomics, emergency medical services, and athlete training assessment.