Triboelectric Effect-Driven Liquid Metal Actuators

Owing to the perfect combination of metallic conductivity, liquid fluidity, and mechanical stability, liquid metals (LMs) are considered the potential materials of the electromechanical system and the basic components of liquid robot. Here, triboelectric effect-driven liquid metal actuators (TLMAs) have been demonstrated, in which the motions of LMs could be driven and accurately controlled by triboelectric nanogenerators (TENGs). By the coulomb forces of transferred triboelectric charges in interdigital electrodes and inertia effects, the LM could be driven for continuous linear and circular motions, respectively. As an alternative structure, the motion of LMs could also be accurately controlled, in which the reciprocating and merging of LMs have been demonstrated. Moreover, the TLMA could serve as a control switch to modulate on/off of an LED by integrating into a circuit, and a transport system based on TLMA has also been demonstrated. In this work, the TENG is used as a medium to first drive and accurately control LMs by external mechanical force, which may have great applications in Micro-Electro-Mechanical System (MEMS), liquid robot, and intelligent microcontroller.