Liquid metal-based dynamic conformal electrodes

Abstract

Electronic skin has increasingly diverse applications in health monitoring, disease diagnosis, rehabilitation therapy, and human-machine interaction. However, most electronic skin devices struggle to maintain stable performance and adhesion under complex conditions involving high body acceleration and sweat. To address these issues, we present a dynamic conformal electrode based on liquid metal, fabricated by coating the semi-liquid metal (SLM) with high conductivity of 9.0 × 10⁶ S/m and low fluidity onto polyborosiloxane (PBS) exhibiting frequency-responsive rheological properties. The gradual deformation of PBS enables SLM to compress into microscopic skin wrinkles while avoiding hair interference. This dynamic conformal electrode can withstand significant deformation exceeding 1,000%, while also increasing the skin contact area, leading to a lower skin contact impedance of 0.1 MΩ at 1,000 Hz and improved interfacial adhesion, maintaining robust skin adhesion for over 7 days. This study demonstrates the capability of the conformal electrode to conduct long-term monitoring of electrocardiogram, electromyogram, and electroencephalogram signals in areas with rough textures, large skin deformation, and dense hair, enabling continuous dynamic monitoring of human health information. The findings highlight its broad potential for applications in health detection, disease diagnosis, rehabilitation therapy, and human-machine interaction.