Abstract

Currently, self-healing soft materials are increasingly applied in flexible electronics, such as intelligent responsive electronic skins and various soft pressure sensors. However, there still exist serious bottlenecks such as complex healing process, severe performance loss after healing, and limitations imposed by external environments, resulting in slow healing speed and deficiencies in healing performance. Liquid metal (LM), as an emerging self-healing material, has been widely adopted in new-generation electronics due to its unique fluidity at room temperature, high surface tension, excellent metallic conductivity, and resistance to extreme environments. Nevertheless, it also faces challenges including low mechanical strength, surface oxidation, complex packaging processes, etc. Researchers have achieved new breakthroughs after combining LM with self-healing materials. This review will conduct an in-depth analysis of the self-healing capability and mechanisms of various LM-based composites, and systematically discuss the common methods for inducing self-healing and reliable characterization techniques. The challenges related to healing speed, efficiency, flexibility and conductivity reliability in electronics are expounded, together with the development opportunities. This provides important guidance for future flexible electronics fields such as self-healing flexible circuits, neural interfaces, robot soft sensors, radiation-resistant self-sealing layers for spacecraft, etc.