Ilkwon Oh1
Korea Advanced Institute of Science and Technology1
Ilkwon Oh1
Korea Advanced Institute of Science and Technology1
Electro-ionic soft actuators, capable of continuous deformations replacing non-compliant rigid mechanical components, attract increasing interest in the field of next-generation metaverse interfaces and soft robotics. Here, we report a novel MXene (Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>) electrode anchoring manganese-based 1,3,5-benzenetricarboxylate metal-organic framework (MnBTC) for ultrastable electro-ionic artificial muscles. By a facile supramolecular self-assembly, the Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>-MnBTC hybrid nanoarchitecture forms coordinate bond, hydrogen bond, and hydrophilic interaction with the conducting polymer of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), resulting in a mechanically flexible and electro-ionically active electrode. The superior electrical and electrochemical performances of the electrode stem from the synergistic effects between intrinsically hierarchical nanoarchitecture of MnBTC and rapid electron transport behavior of Mxene, leading to fast diffusion and accommodation of ions in the ion-exchangeable membrane. The developed artificial muscle based on Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>-MnBTC is found to exhibit high bending displacement (12.5 mm) and ultrafast response time (0.77 s) under a low driving voltage (0.5V), along with wide frequency response (0.1 to 10 Hz) and exceptional stability (98% retention at 43,200 s) without any distortion of actuation performance. Furthermore, the designed electro-active artificial muscle was successfully used to demonstrate mimicry of eye motions including eyelid blinking and eyeball movement in a doll.