Multi-stimulus responsive liquid metals-integrated liquid crystal elastomers actuator with sensing function

Inspired by nature, soft actuators with sensing functions have shown great potential in applications such as dynamic perception, bionic robotics, and smart devices. However, soft actuators with sensing capabilities still suffer from poor stability and slow actuation speed. Herein, the multi-stimulus responsive actuators with sensing functions are fabricated through a judiciously designed amino-functionalized MXene-encapsulated liquid metal nanodroplets (Si-MXene@LM) ink with liquid crystal elastomer (LCE) thanks to strong hydrogen bonding between the -NH and -OH groups to improve stability and actuation speed. When the resulting actuator with sensing function is driven by near-infrared (NIR) light or voltage, it generates a significant actuation strain (45 % in 7 s and 35 % in 15 s) due to the optoelectronic properties of the ink and the excellent responsiveness of the LCE. Importantly, it also has high sensitivity (△R/R 0  = 11.5 %) and outstanding cyclic stability (2500 cycles). As a proof-of-concept, an artificial muscle and intelligent logic circuit based on the actuators demonstrate perfect integration of the actuating and sensing functions, which could not only control of the system, but also sense every actuation state of the actuator. This work is expected to offer new insights into the design of advanced multi-responsive actuators with sensing functions and pave an avenue for the development of multifunctional integrated devices.