Semi-liquid Metal enabled Highly Conductive Wearable Electronics for Smart Fabrics.

Wearable electronics incorporating electronic components into commonly used fabrics can serve as new generation personalized systems for practices ranging from healthcare monitoring to disease treatment. Conventional rigid materials including gold, silver and copper generally require a complicated fabrication process to be sewed into clothes. At the same time, other highly stretchable non-metal materials such as conductive polymers often contain limitations of low electroconductivity, restricting their further applications. Recently, gallium-based liquid metals exhibit superior advantage in flexible electronics and present valuable potential in creative printing technologies. Here, we proposed a novel wearable electronics prepared through roller printing technology based on the adhesion difference of semi-liquid metal (Cu-EGaIn, eutectic gallium-indium mixed with copper micro-particles) on cotton fabrics and polyvinyl acetate (PVAC) glue. Results have shown that the surface topography and chemical interaction of fabrics and PVAC glue determines the adhesion effect with Cu-EGaIn mixture. The conceptual experiments have demonstrated the electromechanical stability of the fabricated wires on fabrics. Further, a series of smart fabrics were developed including interactive circuits, stretchable light emitting diode (LED) array and thermal management device with advantages of easy operation, low cost and large-area fabrication to illustrate practical applications of the method. This strategy would play an important role in future design and fabrication of smart fabrics, contributing to the development of customized healthcare systems.