Liquid metal marbles coated in “nanoparticles” to advance soft electronics

Just one week after announcing a breakthrough nanotechnology material, RMIT University scientists have created droplets of liquid metal coated in nanoparticles, which they claim will advance research into soft electronics and industrial sensing technology.

Scientists at RMIT’s Platform Technologies Research Institute developed “liquid metal marbles” by using functional nanoparticles as a semi-solid coating on liquid metals.

Lead investigator Dr Vijay Sivan said the marbles – which are like flexible ball bearings – were developed as part of investigations into flexible conductive systems for electronic and electromagnetic units.

He told CIO, they had the potential to be used in flexible electronic devices, such as stretchable interconnects for elastic electronic surfaces as well as reconfigurable wires and antennas. Manufacturers such as Samsung have already developed stretchable displays.

The non-stick, durable liquid metal marbles overcome the limitations of liquid metals and enable scientists to use powder coating materials from insulating to semiconducting and highly conducting, Dr Sivan said.

“The idea of building liquid electronics based on liquid metal marbles is unique, as they can not only move and form makeshift electronic devices, they can also produce strong plasmonic fields around them,” he said.

“For sensing applications, these marbles are the safest alternative to mercury-based heavy metal ion sensors, while their thermal conduction properties are also fascinating, and should be further investigated.”

Sivan said the marbles can “endure high impacts and temperatures without disintegrating, can operate like semiconducting systems, and are compatible with micro and nano-fluidic systems.

Sivan said that when solid metal is used in a "flexible electronic environment" it becomes damaged and disintegrates. However, liquid metal "actually self-heals" making it suitable to use in flexible electronic devices in the future.

The discovery follows news earlier this week that a separate RMIT research team – working with scientists from the CSIRO – created a new two-dimensional nano-material that may help manufacturers create even smaller computing devices that offer significant improvements in processing speed.