Ion-driven actuators based on two-dimensional nanomaterials: Microstructures, mechanisms, performance, applications, and future perspectives

Two-dimensional (2D) nanoporous materials have emerged as a prominent class of advanced functional materials due to their exceptional structural tunability, rich surface chemistry, and outstanding physicochemical properties. In recent years, the rapid advancement of emerging technologies such as flexible electronics, intelligent bionic systems, and microrobotics has driven a growing demand for high-performance actuation materials. Ion-driven actuators constructed from representative 2D nanomaterials, including MXenes, metal-organic frameworks (MOFs), and molybdenum disulfide (MoS₂), have attacted considerable attention owing to their superior ion responsiveness, high energy conversion efficiency, excellent flexibility, and high designability. These characteristics make them promising candidates for next-generation artificial muscles and flexible intelligent actuation systems. This review systematically summarizes the microstructure, working mechanisms, actuation performance, multifunctional applications, and future perspectives of ion-driven actuators based on MXenes, MOFs, and MoS₂. First, the fundamental properties, microstructural features, and tunability strategies of these materials are discussed, with an emphasis on integrated design concepts for achieving structure–function synergy in ion-responsive actuation systems. Subsequently, the actuation mechanisms under electrical stimulation are elucidated, focusing on ion migration, electrochemical reactions, and surface charge redistribution. Furthermore, a comparative analysis of the actuation performance of different material systems is presented, along with a discussion of their potential applications in frontier fields such as flexible electronic devices, biomimetic engineering systems, and micro/nanoelectromechanical systems (MEMS/NEMS), highlighting their immense potential in realizing multifunctional intelligent systems. Finally, the current challenges including issues related to structural control, mechanistic understanding, and material performance optimization are identified, and future research directions are proposed. This review aims to provide theoretical insights for the design and optimization of high-performance ion-driven actuators and to promote their practical implementation and industrial translation in flexible intelligent systems.