- DGIST develops passive cooling film that absorbs moisture from air and releases it as vapor when heat builds up

- Sustained temperature drop of up to 18.2°C for more than 12 hours; targets data centers and electric vehicle batteries

The synthesized material is transparent and flexible when fully dry, allowing it to be applied to the surfaces of a wide range of electronic devices. [Provided by DGIST]
The synthesized material is transparent and flexible when fully dry, allowing it to be applied to the surfaces of a wide range of electronic devices. [Provided by DGIST]

Amid soaring power and water consumption at data centers driven by the spread of AI, researchers have developed a new material that cools electronic devices on its own without electricity or coolant. The film absorbs moisture from the surrounding air, stores it, and then releases it as vapor when a device heats up. In laboratory tests, it kept device temperatures down by as much as 18.2 degrees Celsius for more than 12 hours.

The Daegu Gyeongbuk Institute of Science and Technology (DGIST) announced that a research team led by Professor Kim Sung-kyun of the Department of Chemistry and Physics developed a "passive cooling film" that lowers the temperature of electronic devices using only ambient moisture, with no external energy supply.

Heat is one of the biggest challenges facing high-performance electronics — from AI data centers to smartphones, laptops and electric vehicle batteries. Data centers in particular require substantial electricity and cooling water to dissipate the enormous heat generated by their servers. Conventional active cooling systems that rely on fans and pumps bring additional power consumption, complex infrastructure and ongoing maintenance costs.

The research team turned to evaporative cooling, which requires no external energy. The approach harnesses the principle that evaporating water draws heat away from its surroundings and applies it to electronic device cooling.

The key challenge was how effectively the material could capture and retain moisture from the air. Most existing hygroscopic materials are rigid crystalline solids that are difficult to bond closely to device surfaces and risk corroding metals and other materials when they absorb moisture.

The team combined nanocellulose, which has excellent moisture-storage capacity, with organic ionic molecules that exhibit strong hygroscopicity. The result is a film that absorbs moisture readily while remaining flexible and highly adhesive.

Even in a fully dry state, the film adheres seamlessly to a wide range of surfaces, including metals, semiconductors and glass. In dry conditions it absorbs and stores moisture from the air, then releases that moisture as vapor when the device generates heat during operation, drawing thermal energy away from the surface. The film does not corrode devices even when saturated with moisture, meaning it can be applied directly without a separate protective coating.

The research team of Professor Kim Sung-kyun (second from left) of DGIST's Department of Chemistry and Physics. [Provided by DGIST]
The research team of Professor Kim Sung-kyun (second from left) of DGIST's Department of Chemistry and Physics. [Provided by DGIST]

The cooling performance has been verified. When the film was applied under conditions simulating continuous operation of an actual electronic device, the surface temperature fell from 72.3 degrees Celsius to 54.1 degrees — a reduction of up to 18.2 degrees that held stable for more than 12 hours.

The research team believes the film could serve as a supplementary cooling solution for AI data centers and server rooms, as well as in smartphones, laptops, wearable devices and electric vehicle batteries. Its high flexibility and adhesiveness make it particularly well suited for electronics with tight spaces or curved surfaces.

Commercialization is expected to take roughly three to five years. The team still needs to secure process technology capable of mass-producing large-area films and to verify that cooling performance remains stable across a range of industrial and climatic environments with varying temperatures and humidity levels.

"We have proposed a path that simultaneously overcomes the corrosiveness and the lack of flexibility and adhesiveness that have limited existing passive cooling materials," Kim said. "Beyond being a simple eco-friendly material, this could become a new alternative for solving the heat-management challenges facing electronic devices."

The findings were published in the September issue of the international academic journal Small Structures.


nbgkoo@heraldcorp.com