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Abstract Liquid metals, such as Gallium‐based alloys, have unique mechanical and electrical properties because they behave like liquid at room temperature. These properties make liquid metals favorable for soft electronics and stretchable conductors. In addition, these metals spontaneously form a thin oxide layer on their surface. Applications made possible by this delicate oxide skin include shape reconfigurable electronics, 3D‐printed structures, and unconventional actuators. This paper introduces a new approach where liquid metal oxide serves as an electrochemical energy source. By mechanically rupturing their surface oxide, liquid metals form a galvanic cell and convert their chemical energy to electrical energy. When dispersing liquid metals into an ionically‐conductive liquid to form emulsions, this composite material can provide ∼500 mV of open‐circuit voltage and up to ∼4 μWof power. Protected by the naturally occurring oxide skin, the passivating oxide layer of the liquid metal shields it from self‐discharge over time. The device is also stable in harsh environments, such as high temperature or aquatic conditions. Future applications of this device are demonstrated by designing a strain‐activated stretchable battery and a pressure‐sensitive self‐powered keypad. These findings may unlock new pathways to design stretchable batteries and harness their inherent energy for self‐powered robust devices.
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This content will become publicly available on May 1, 2026
Realizing nanostructure-enabled applications through dealloyed materials
Nanoporous metals produced via dealloying have attracted significant interest due to the interesting physics surrounding their morphological evolution and how their topologically complex structure influences mechanical, optical, and electrochemical properties. Their impressive nanostructure-enabled properties – such as increased catalytic activity, surface-enhanced Raman signals, high strength and large surface-to-volume ratio – have led to catalysts, sensors, actuators, energy storage, and biomedical device coatings with superior properties and performance. However, translation of nanoporous metals into practical applications has revealed needs for new material systems and manufacturing approaches, and consequently better predictive models for application-specific operating conditions. The goal of this MRS Bulletin issue is to elaborate on the latest advances in emerging methods and technologies of dealloyed materials that enable new structures and form factors, machine learning-guided design and synthesis, material recovery and sustainability for scaled-up production, and stable performance in intended operational environments.
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- Award ID(s):
- 2003849
- PAR ID:
- 10636120
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- MRS Bulletin
- Volume:
- 50
- Issue:
- 5
- ISSN:
- 0883-7694
- Page Range / eLocation ID:
- 599 to 607
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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