New Liquid Metal Powder Technology Revolutionizes Flexible Electronics with Direct-Draw Circuits
Researchers from the Korea Advanced Institute of Science and Technology (KAIST) and the Electronics and Telecommunications Research Institute (ETRI) have developed a new electronic materials technology. This innovation utilizes liquid metal in a fine powder form, allowing for the direct drawing of electrical circuits on a variety of surfaces.
"This innovation aims to advance next-generation flexible electronics, including applications in soft robotics and wearable health monitoring devices."
Overcoming Conventional Liquid Metal Limitations
Traditional liquid metals, while electrically conductive, exhibit high surface tension and poor wettability on most surfaces, making precise circuit creation challenging due to spreading or clumping. Previous methods often required additional surface treatments or processing steps, limiting their practical application.
The Liquid Metal Powder Innovation
The research team's approach converts liquid metal into fine powder particles. Each particle is encased in a thin oxide shell, which forms naturally when the metal interacts with air. Initially, the powder is non-conductive.
- When light mechanical stimulation (e.g., brushing or pressing with a finger) is applied, the oxide shell breaks.
- This action allows the metal particles to connect, enabling electrical conductivity.
This method allows users to apply the powder to a surface and then activate only the desired areas by pressing them, overcoming the spreading and patterning difficulties associated with conventional liquid metal circuits.
Versatility and Applications
This technology enables the creation of circuits instantly, without requiring thermal processing, on diverse materials such as paper, glass, plastic, textiles, and even living plant leaves. This approach reduces issues like spreading, sedimentation, and pattern distortion common in previous liquid metal circuit methods.
"Practical applications demonstrated include skin-mounted wireless health monitoring devices and flexible circuits for soft robots."
Environmental Sustainability
After use, the circuits can be dissolved in water and chemically treated (e.g., with sodium hydroxide) to recover the liquid metal.
"The recovered metal can then be reprocessed into powder form and reused, offering an environmentally friendly method to reduce electronic waste."
Stable Performance
The developed powder maintains its functionality for over a year when stored at room temperature. It also remains electrically functional after tens of thousands of bending or twisting cycles, making it suitable for both temporary and customizable electronic devices.
Researcher Statements and Publication Details
Distinguished Professor Inkyu Park stated that the research allows for intuitive circuit fabrication and material recycling, anticipating applications in wearable computing and adaptive IoT systems.
The study, led by postdoctoral researcher Osman Gul from KAIST, was published online on December 9, 2025, in the international journal Advanced Functional Materials. It was also recognized as the journal's Back Cover article. The research was supported by the Mid-Career Researcher Program of the National Research Foundation of Korea (NRF).