Multiphase mixtures containing both liquid metal and solid inclusions in a soft polymeric matrix can exhibit unique combinations of mechanical, electrical, magnetic, and thermal properties. Gallium‐based liquid metals have excellent electrical and thermal properties, and incorporating additional conductive, magnetic, or other solid fillers into liquid metal‐embedded elastomers can yield heightened electrical and thermal conductivities, enhanced elasticity due to lowered percolation thresholds, and positive piezoconductivity. This emerging class of liquid metal + x composites, where x denotes any solid filler type, has applications in stretchable electronics, wearables, soft robotics, and energy harvesting and storage. In this review, the recent literature is consolidated on liquid metal + x composites and their potential to offer uniquely amplified or multiplied bulk properties is highlighted. The literature related to the materials and processing of liquid metal + x composites is reviewed, through which it is found that the properties of the resulting multiphase composites are sensitive to the sequence in which the distinct liquid metal and solid inclusions are incorporated into the continuous phase. This review further includes a summary of relevant predictive modeling approaches, as well as identifies grand challenges and opportunities to advance liquid metal + x composites.
This review highlights the unique techniques for patterning liquid metals containing gallium (e.g., eutectic gallium indium, EGaIn). These techniques are enabled by two unique attributes of these liquids relative to solid metals: 1) The fluidity of the metal allows it to be injected, sprayed, and generally dispensed. 2) The solid native oxide shell allows the metal to adhere to surfaces and be shaped in ways that would normally be prohibited due to surface tension. The ability to shape liquid metals into non‐spherical structures such as wires, antennas, and electrodes can enable fluidic metallic conductors for stretchable electronics, soft robotics, e‐skins, and wearables. The key properties of these metals with a focus on methods to pattern liquid metals into soft or stretchable devices are summari.
more » « less- PAR ID:
- 10413942
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 19
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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