Researchers develop new technique to keep smartphones cool by sweating

Researchers have developed a technique to keep smartphones cool. A new rmal manment method has been developed that aims to prevent smartphones and laptops from heating up, by releasing water vapor. As described in journal Joule, this new method could keep electronics cooler, unlike existing strategies, by dissipating excess heat.

" development of microelectronics puts great demands on efficient rmal manment techniques because all components are tightly packed, and chips can get really hot," said Ruzhu Wang, from Shanghai Jiao Tong University in China.

"For example, without an effective cooling system, our phones could have a system breakdown, and burn our hands if we run m for a long time, or load a big application," Wang said in a statement.

research tes that larger devices such as computers use fans to regulate temperature. Given bulkiness, ise and energy consumption of fans, y are t suitable for smaller devices like mobile phones, researchers said.

Although manufacturers have been using phase change materials (PCMs) like waxes and fatty acids for cooling phones by absorbing heat produced by devices when materials melt, total amount of energy exchanged during solid-liquid transition is relatively low.

In comparison, liquid-vapor transition of water can exchange 10-times energy compared to that of PCM solid-liquid transition. Researchers also studied a group of porous materials that can absorb moisture from air, and release water vapor when heated.

Researchers found Metal-organic frameworks (MOFs) most promising because y could store a large amount of water and take away more heat when heated. Previously, researchers have tried to use MOFs to extract water from desert air.

"Our study shows electronics cooling is a good real-life application of MOFs. We used less than 0.3 grams of material in our experiment, and cooling effect it produced was significant," Wang said.

researchers selected a type of MOFs called MIL-101(Cr) for experiment because of its good water-absorbing capacity, and high sensitivity to temperature changes. y coated three 16-square-centimeter aluminum sheets with MIL-101(Cr) of different thicknesses -- 198, 313, and 516 micrometers, respectively -- and heated m on a hot plate.

team found that MIL-101Cr coating was able to delay temperature rise of sheets, and effect increased with coating thickness. While an uncoated sheet reached 60 degrees Celsius after 5.2 minutes, thinnest coating doubled time, and didn't reach same temperature until 11.7 minutes, researchers said.

Researchers said that sheet with thickest coating reached 60 degrees Celsius after 19.35 minutes of heating.

(With inputs from PTI)