Al-NaOH-Composited Liquid Metal:A Fast-Response Water-Triggered Material with Thermal and Pneumatic Properties

摘要

Water-triggered materials are receiving increasing attentions due to their diverse capabilities such as easy operation,soft actuation,low cost,environmental friendliness,and many more other advantages.However,most of such materials generally have a long reaction time and require strict preservation conditions,which limit their adaptability in practice.In this study,a novel water-triggered material based on Al-NaOH-composited eutectic gallium–indium(eGaIn)alloys was proposed and demonstrated,which is rather fast-responsive and deformable.Once water is applied,the material thus fabricated would achieve a temperature rise of 40C in just several seconds along with gas production,indicating its big potential to be used as a thermal and pneumatic actuator.Further,the new material’s reusability and degradation ability were also tested.Following that,a double-layer-structure smart bandage was designed,whose bulk was filled with Al-NaOH-composited eGaIn while BiInSn served as outer supporting material.According to the experiments,a sheet structure with a thickness of 2 mm would support a weight of 1.8 kg after it was subjected to a cooling process,which is much better than the weight-bearing capability of fiberglass.In addition,a prototype of a water-triggered sphere robot was also fabricated using Al-NaOH-eGaIn,which realized rolling and bouncing behaviors under specific external stimulation.These findings indicate the potential value of the present material in developing future wearable devices,soft actuators,and soft robotics.