3D printed self-healing, degradable on-skin electronics with liquid metal for multi-functional monitoring

Soft, flexible electronics is boosting the monitoring physiological data and assessing health conditions. However, their further practical utilization is limited due to the lack of intrinsic adhesion interfaces for mechanical deformation, self-healing capability against mechanical damages, and degradable properties for the waste electronic products treatment. Herein, we report the design concepts, materials, fabrication methods, and multifunctional applications of a new type of self-healing and degradable flexible health-detection electronics based on three-dimensional (3D) printable polymers and liquid metals. The 3D printed elastomer processes amazing self-healing efficiency (99.5 %), excellent mechanical properties (tensile strength: 3104 kPa), degradable, intrinsic adhesion, etc. Polymer elastomers combined with the fluidity of Galinstan (GaInSn) allow the electronic devices to heal from fracture and restore electrical performance. Our polymer elastomers effectively solve the coordination problems between solid-state electronic devices and substrates, greatly improving the integration and functional complexity of the functional devices. The reliable connection between the GaInSn circuit, commercial components and elastomers can easily measure various physiological signals such as electrophysiology, temperature, and body motions. In addition, the commercial components and GaInSn circuits can be well recycled through ethanol to reduce pollution to the environment. The present 3D printed self-healing multi-functional electronics enables new opportunities for promising applications of flexible electronic devices.