Magnetic, conductive and multifunctional flexible alginate/Ti₃C₂T_x MXene hydrogel sponge with uniformly oriented...

With the rapid development of the next generation of intelligent wearable electronics, functional flexible biopolymer hydrogel sponges capable of simultaneously detecting multiple stimuli and processing interactive information have attracted incremental attentions. Despite being a natural macromolecule with diverse structure, achieving high cross-sensitivity, excellent response linearity, and reliable working life simultaneously under multiple stimuli remains a challenge for alginate-based hydrogel sponges. Herein, a multifunctional biological macromolecular hydrogel is designed by decorating elastic sodium alginate/polyvinyl alcohol scaffold with soft magnetic particles and Ti₃C₂T_x MXene network in an efficient directional ice template method. Based on the uniformly oriented porous structure and double-interface locked Ti₃C₂T_x MXene conductive network, the proposed hydrogel sponges not only display impressive magnetic sensing performance, including high sensitivity and quick response, but also exhibit excellent strain and pressure sensing capabilities, characterized by superior cross-sensitivity, and long-term stability. Furthermore, the assembled sensor array showcases favorable capability for detecting spatial distribution of temperature, pressure and magnetic field signals in real time. Additionally, with an aid of machine learning, a wearable sensor array can successfully achieve gesture recognition with high accuracy of 98.5 %, enabling real-time control of the robot.