Multi-Responsive SEBS/MXene Janus Membranes Enabling Piezoelectric Energy Harvesting, Humidity Sensing, and Infrared Stealth

In response to the urgent need for multifunctional integration in flexible intelligent systems, as well as the limitations of traditional multilayer integration strategies in terms of interface and mechanical performance, inspired by the intrinsic asymmetry of natural Janus structures, this study designed and prepared a novel flexible styrene-ethylene-butylene-styrene (SEBS)/MXene (SM) Janus fibrous membrane. Under mechanical pressure, the SM Janus membrane can generate a remarkable piezoelectric output of up to 28 V and 133 nA, sufficient to drive humidity sensing, thereby establishing a self-powered sensing-energy supply closed-loop system. The synergistic interaction between the hydrophilic MXene layer and the hydrophobic SEBS layer enables the humidity sensor to exhibit high sensitivity and rapid response characteristics, with response and recovery times of 0.79 and 0.35 s, respectively. This allows for effective monitoring of respiration, ambient humidity, and speech signals. Furthermore, the membrane demonstrates exceptional infrared camouflage performance, with an emissivity as low as 32%, significantly modulating the apparent temperature of targets. This study pioneers the integration of energy harvesting, self-powered sensing, and adaptive camouflage into a single material platform, showcasing broad application prospects in fields such as bionic electronic skin and environmental interactive systems.