Antioxidative ultrafast light-driven poly(N-isopropylacrylamide) hydrogel actuator enabled by (3-aminopropyl)triethoxysilane-modified MXene and polyvinyl alcohol

Developing hydrogel actuators with excellent driving performance and extended lifespan remains challenging. Ti 3 C 2 T x MXene, as a two-dimensional nanomaterial with a unique layered structure, has attracted widespread attention in flexible hydrogel actuators for its excellent optical absorption properties and tunable surface functionality. However, MXene faces difficulties in dispersion and is prone to oxidation, which significantly hinders the development and use of MXene-based hydrogel actuators. In this study, we fabricated a near-infrared light-driven hydrogel actuator with rapid photo responsiveness and antioxidative properties by incorporating modified MXene with antioxidant characteristics and the pore-forming agent polyvinyl alcohol into the poly( N -isopropylacrylamide) (PNIPAM) hydrogel system. We functionalized MXene nanosheets with (3-aminopropyl)triethoxysilane (APTES), effectively enhancing antioxidative properties, preventing structural degradation caused by spontaneous oxidation, and improving surface properties. This enhanced the dispersion stability of MXene in the system and extended its lifespan from 7 days to over two weeks. The hydrophilic polyvinyl alcohol chains served as drainage channels during hydrogel contraction, imparting the hydrogel with rapid driving capabilities (127.1° s −1 ). Additionally, leveraging the fast response characteristics, we designed an octopus-inspired light-driven soft swimmer and gripper. This work provides novel insights into the application of intelligent responsive hydrogels in biomimetic and practical scenarios. Graphical abstract