Wearable electronics, conformable sensors, and soft/micro-robotics require conductive yet stretchable thin films. However, traditional free standing metallic thin films are often brittle, inextensible, and must be processed in strict environments. This limits implementation into soft technologies where high electrical conductivity must be achieved while maintaining high compliance and conformability. Here we show a liquid metal elastomeric thin film (LET) composite with elastomer-like compliance (modulus < 500 kPa) and stretchability (>700%) with metallic conductivity (sheet resistance < 0.1 Ω/□). These 30–70
This paper reports soft and stretchable films of liquid metal particles (LMPs) that offer high surface area and high conductivity. Liquid metals (LM) based on gallium are compelling conductors for soft and stretchable devices, yet it is difficult to make electrodes of LM with high surface area due to the tendency of liquids to minimize their surface area. To form films of percolated particles with high surface area, LMPs are first created by sonicating LM in isopropanol with trace amounts of hydrochloric acid and 1,6‐hexane dithiol to decrease the amount of surface oxide on the LMPs. A film of these particles placed on a tacky substrate is initially insulating but percolate into conductive paths by straining the substrate. The resulting electrode has high conductivity (1.64 × 105S m−1) and high surface area (1257% greater than a bulk LM film with the same areal footprint). Interestingly, these electrodes have nearly strain‐invariant resistance (
- NSF-PAR ID:
- 10401113
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 8
- Issue:
- 5
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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