Novel two-dimensional conductive metal–organic framework-based heterostructures for high-performance electro-ionic soft actuators†

Abstract

Current ionic artificial muscle technology necessitates a significant technological advancement to achieve increased bending strain, enhanced response rates, and prolonged stability while ensuring consistent and reliable performance across various stimuli. In this study, we aimed to develop an artificial muscle based on a novel nanocomposite composed of ionically cross-linked ZnO@Zn-CAT with poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), showing an ultrafast rise time of less than 1.56 s in DC responses, an extremely large bending strain up to 1.22% in a very low input voltage regime (0.1 to 3 V), a long-term cycling stability of 97% up to 10 000 cycles, markedly reduced phase delay, and a very broad frequency bandwidth up to 20 Hz with good structural reliability under continuous electrical stimuli. Most importantly, the proposed ZnO@Zn-CAT-based soft actuator exhibits a remarkably enhanced strain of 2.38% and a blocking force of 66 mN under an extra 700 nm light stimulation, allowing for the realization of complex next-generation soft robotic devices, including wearable electronics and artificial muscles.