Flexible MXene composed triboelectric nanogenerator via facile vacuum-assistant filtration method for self-powered biomechanical sensing

With the explosive development of sensing systems in miniaturization, intelligence, multi-function and networking, triboelectric nanogenerator (TENG) with simple structure, low cost and self-powering characters has become an excellent candidate for mechanical sensors. However, it remains a great challenge to obtain a stable interface of electrode and triboelectric layers for timely and long-term triboelectric surface charges transfer. In this study, through a simple vacuum-assistant filtration method, we prepared an integrated MXene-PEDOT:PSS/PTFE (MXene-poly(3,4-ethylenedioxythiophene):Poly (styrenesulfonate)/polytetrafluoroethylene) (MPP) film as the electrode and triboelectric layer of TENG for self-powered sensing. The TENG-based sensor has a high sensitivity especially to tiny forces (>6.05 V·N⁻¹) with short response (52 ms) and recovery (34 ms) time, as well as an excellent stability (over 6000 cycles). The fabrication method is suitable for most conductive nanomaterials, and the triboelectric layer can be replaced with other commercialized filter films, such as cellulose and mixed fiber resin (MFR). It provides a simple and versatile method for the preparation of stable electrode-triboelectric interface, and has broad prospects in TENG-based wearable sensors.