Abstract Liquid metals (LMs), renowned for their high conductivity and large deformability, find increasing applications including in flexible electronics and soft robotics. One critical process in these applications is the precise patterning of LMs into desired shapes. Yet, existing LM patterning techniques predominantly focus on 2D patterns due to challenges posed by the inherent fluidity and leakage of LMs. Here, we introduce an approach that bypasses these limitations, enabling the creation of complex 3D leakage‐free LM structures. This is achieved through mechanical programming of 2D magnetically immobilized LM paste formed via incorporating magnetic particles into LMs. Such composite effectively resists leakage due to the combined effect of strong magnetic inter‐attraction within the porous magnetic networks and the high surface tension of LMs, while retaining the high conductivity. Diverse freestanding magnetic LM structures, obtained upon LM solidification at ambient temperature, dynamically morph between their 2D and various 3D configurations through multiple cycles of induction heating and magnetic‐assisted reprogramming, featuring large compression resistance and self‐healing capabilities. Potential applications of these leakage‐resistant, shape‐adaptable structures are demonstrated through a helical magnetic LM antenna, which showcases its efficiency in wireless communication and energy harvesting.
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Functional heterophasic liquid metals
Abstract Liquid metals (LMs) have compelling applications in stretchable electronics, wearable devices, and soft robotics ascribing to the unique combination of room temperature fluidity and metallic electrical/thermal conductivity. Adding metallic elements in gallium‐based LMs can produce heterophasic (i.e., solid and liquid) LMs with altered properties including morphology, surface energy, rheology, electrical/thermal conductivity, and chemical reactivity. Importantly, heterophasic LMs can respond to external stimuli such as magnetic fields, temperature, and force. Thus, heterophasic LMs can broaden the potential applications of LMs. This report reviews the recent progress about heterophasic LMs through metallic elements in the periodic table and discusses their functionalities. The heterophasic LMs are systematically organized into four categories based on their features and applications including electrical/thermal conductivity, magnetic property, catalysis/energy management, and biomedical applications. This comprehensive review is aimed to help summarize the field and identify new opportunities for future studies.
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- Award ID(s):
- 2032409
- PAR ID:
- 10496546
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Responsive Materials
- Volume:
- 1
- Issue:
- 1
- ISSN:
- 2834-8966
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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