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Electronics should sweat to cool down, say researchers
Computing devices should sweat when they get too hot, say scientists at Shanghai Jiao Tong University in China, where they have developed a materials application they claim will cool down devices more efficiently and in smaller form-factors than existing fans.
It’s “a coating for electronics that releases water vapor to dissipate heat from running devices,” the team explain in a news release. “Mammals sweat to regulate body temperature,” so should electronics, they believe.
The group’s focus has been on studying porous materials that can absorb moisture from the environment and then release water vapor when warmed. MIL-101(Cr) checks the boxes, they say. The material is a metal organic framework, or MOF, which is a sorbent, a material that stores large amounts of water. The higher the water capacity one has, the greater the dissipation of heat when it’s warmed.
MOF projects have been attempted before. “Researchers have tried to use MOFs to extract water from the desert air,” says refrigeration-engineering scientist Ruzhu Wang, who is senior author of a paper on the university’s work that has just been published in Joule.
Their proof-of-concept test involved applying a micrometers-thin coating of MIL-101(Cr) to metallic substrates that resulted in temperature drops of up to 8.6 degrees Celsius for 25 minutes, according to the abstract for their paper.
That’s “a significant improvement compared to that of traditional PCMs,” they say. Phase change materials (PCM) include waxes and fatty acids that are used in electronics and melt to absorb heat. They are used in smartphones, but the solid-to-liquid transition doesn’t exchange all that much energy.