Endowing Conventional Materials with Advanced Functions via Liquid Metals: A Route Toward Intelligent Material Systems

The growing demand for soft and adaptive technologies requires materials that can sense, respond, and operate reliably under complex mechanical and environmental conditions. However, most smart materials are constructed through de novo synthesis or multi-step chemical design, making them difficult to customize and challenging to integrate with established material systems. Room-temperature liquid metals provide a practical route by imparting electrical, thermal, mechanical, and electrochemical functions to conventional materials through surface, interfacial, or confined integration, without requiring redesign of the host material framework. This review summarizes recent advances in liquid-metal-enabled intelligent functions and categorizes integration strategies into surface coating, encapsulation, layered integration, and bulk compositing. These approaches allow materials including, polymers, textiles, rigid materials, and biocompatible substrates, to achieve capabilities such as stretchable sensing, adaptive actuation, thermal regulation, energy harvesting, and oxide-mediated resistive memory. The behaviors arise from the fluidity, interfacial chemistry, and phase tunability of liquid metals, which support responses not attainable with solid fillers. Key challenges including interfacial stability, long-term reliability, scalable processing, and sustainable material choices are discussed, along with opportunities in programmable multi-field responses, data-driven design, and standardized manufacturing. Liquid metal integration offers a broadly applicable route to transform common materials into intelligent systems with minimal processing complexity.