Electroactive soft actuators and bioinspired artificial muscles have received burgeoning interest as essential components in future electronic devices such as soft haptic-feedback systems, human-friendly wearable electronics, and active biomedical devices. However, important challenging issues including fast response time, ultralow input power, robust operation in harsh environments, high-resolution controllability, and cost-effectiveness remain to be resolved for more practical applications. Here, an electroionic antagonistic artificial muscle is reported based on hierarchically porous nitrogen-doped carbon (HPNC) electrodes derived from a microporous poly(triazine-triptycene) organic framework (PtztpOF). The HPNC, which exhibits hierarchically micro- and mesoporous structures, high specific capacitance of 330 F g-1 in aqueous solution, large specific surface area of 830.46 m2 g-1, and graphitic nitrogen doping, offers high electrical conductivity of 0.073 MS m-1 and outstanding volumetric capacitance of 10.4 MF m-3. Furthermore, it is demonstrated that a novel electroionic antagonistic muscle based on HPNC electrodes successfully displays extremely reliable and large bending deformations and long-term durability under ultralow input voltages. Therefore, microporous polymer or covalent organic frameworks can be applied to provide significant improvements in electroactive artificial muscles, which can play key roles as technological advances toward bioinspired actuating devices required for next-generation soft and wearable electronics.
Keywords: actuator; artificial muscle; covalent organic framework; hierarchically porous nitrogen doped carbon; specific capacitance.