A smart triboelectric nanogenerator with tunable rheological and electrical performance for self-powered multi-sensors

Abstract

A smart magnetorheological elastomer (MRE)-based triboelectric nanogenerator (TENG) with tunable electric–mechanical performance has been developed by assembling MREs, Cu foil and metal wires. The MRE polymer, composed of carbonyl iron and a shear stiffening elastomer matrix, shows a high response to a magnetic field, and the MR effect is 114.68% with a maximum storage modulus of 0.77 MPa. The TENG presents a positive triboelectric performance (PTP) with an increase in the loading pressure. It generates a maximum power of 55.07 μW with a voltage of 20.99 V and lights up 39 LEDs, which proves the high mechanical energy-harvesting properties. More interestingly, the TENG shows a negative triboelectric performance (NTP) under the excitation of a magnetic field owing to the high MR effect and saturated magnetization value of 147.51 emu g⁻¹. Therefore, the overall triboelectric properties of the TENG can be precisely manipulated by alternating the external multi-fields. In addition, the intelligent TENG, with a fast response and high flexibility, functions as a portable self-powered sensor to monitor human motion, distinguish various contact materials, and perceive external magnetic fields. To this end, this work opens up a new avenue to develop a smart TENG device with tunable rheological and triboelectric properties and the self-powered wearable sensor could detect complex multi-field circumstances, which proves it has promising applications in smart energy generation systems and wearable multi-sensing electronics.