Liquid metal extreme materials

The continuous advancement of materials and technologies has significantly propelled the progress of human civilization. However, the more humans achieved, the more bottlenecks we encounter which span from space exploration, cutting edge advanced cooling to the clinical therapy of a single malignant tumor. The revolution to break through such barriers lies in the identification of extreme materials that can easily tackle the existing challenges and fundamentally extend the technological boundary, thus potentially leading to the creation of entirely new devices and systems. The emergence of room-temperature liquid metals (LMs) with their unique characteristics and diverse unconventional capabilities distinguished from traditionally developed electrical, soft, and fluidic materials, is anticipated to revolutionize a broad range of interdisciplinary fields. This review is dedicated to extracting the extreme features of LMs and systematizing their distinct applied scenarios from pervasive electronic fabrication to thermal management, and healthcare systems until human-like transformable robotics. The prospects and challenges of LM extreme materials are outlined. It is expected that further investigations on the clarified scientific and technological categories lying behind will contribute well to the next generation human civilization in the coming time.