Gallium-Based Liquid Metals: From Fundamental Properties to State-of-the-Art Applications

The rapid advancement of flexible and stretchable electronics has raised new demands for conductive materials with high conductivity and excellent mechanical properties. Compared to traditional conductive materials, gallium-based liquid metals exhibit a compelling set of attributes-including intrinsic deformability, high conductivity, good thermal conductivity, and a liquid state at or near room temperature-that address the critical requirements for conductors in flexible and stretchable electronics. However, the broader application of gallium-based liquid metals is limited by intrinsic challenges, such as oxidation tendency and high surface tension, while their multifunctional potential remains to be fully explored and developed. This paper provides a comprehensive review of gallium-based liquid metals, spanning from their fundamental concepts including intrinsic properties and processing characteristics (oxidative layer/droplet engineering) and functionalization techniques to their diverse applications in flexible electronics. It concisely summarizes key factors, existing issues, and challenges encountered during the design, research, and application of gallium-based liquid metals, aiming to provide guidance and assistance for subsequent research and applications.