Molecular Engineering of MXene-Covalent-Triazine Framework Interfaces for Electrochemical Actuators

Developing multifunctional nanomaterials for soft electrochemical actuators and energy storage devices is crucial for advancing next-generation soft robotics, wearable electronics, and bioinspired technologies. However, existing electrode materials face fundamental trade-offs among electronic conductivity, charge storage capacity, and ion transport efficiency. Here, we report a molecularly engineered hybrid nanoarchitecture that achieves the physicochemical stabilization of MXene terminals by the <i>in situ</i> growth of 4<i>H</i>-pyran functionalized, electronically conjugated covalent-triazine frameworks (MXene-CTF). The integration of MXene and CTFs forms a synergistic active electrode for superior supercapacitors and actuators by offering significantly enlarged interactive surface areas, a well-developed network of nanoporous channels, and enhanced electrical conductivity. The MXene-CTF electrode provides an eminent energy density of 159.8 Wh kg^-1 at a power density of 150 W kg^-1 in a supercapacitor configuration with a nonaqueous ionic liquid electrolyte. Also, it achieves a bending strain of 1.1% and a blocking force of 5.8 mN, with a rapid response time of 1.4 s and a phase delay of 0.15 rad under an ultralow input potential of 0.5 V in a soft actuator configuration. This work unveils a strategy for the molecular-level synergistic integration of MXene with CTFs, offering a promising pathway for the development of high-performance energy storage and electrochemical actuation technologies.