High‐Performance MXene/Carbon Nanotube Electrochemical Actuators for Biomimetic Soft Robotic Applications

Abstract Ionic electrochemical actuators, which convert electrical energy into mechanical energy through electrochemical‐induced ion migration, show great potential in biomimetic soft robots. However, their applications are still limited due to the influence of the electrode materials and actuator performance. Here, an MXene/carbon nanotube (CNT) heterostructural electrode‐based ionic actuator is developed and realizes dexterous touch manipulation mimicking humans. In this MXene/CNT heterostructure, one‐dimensional CNTs are chemically interconnected into layered two‐dimensional MXene nanosheets, increasing their interlayer spacing, promoting mechanical stability, and enhancing specific surface area, which facilitates the ion migration and storage as well as electrochemical actuation. Accordingly, the MXene/CNT actuator can output excellent mechanical deformation under 2.5 V voltage, including large peak‐to‐peak deformation (displacement 24 mm, strain 1.54%), wide frequency response (0.1–15 Hz), large force (5 mN) and good cycling stability. The actuators can be used to construct artificial fingers to achieve gentle, multi‐point, variable frequency, and synergistic touching on fragile smartphone screens, including pressing a phone number to make a call and tapping an electronic drum. Especially, this finger can tap the drum at a high frequency (13 Hz), exceeding the tapping frequency that real human fingers can reach, which demonstrates its prospect in human‐computer interaction.