The growing need to keep mobile phones and other portable electronic devices cool spurred researchers from Shanghai Jiao Tong University, China, to devise an effective passive thermal management solution. Device overheating can be prevented by application of a metal organic framework (MOF)-based coating that absorbs 
The coating releases water vapor to dissipate heat from electronic devices. Source: C. Wang et al. moisture from air and releases water vapor when heated.
Chromium terephthalate MOF was tested as a sorbent by coating a layer on metallic sheets with applied thicknesses in the 198 to 516 micrometer range. When heated on a hot plate, an uncoated sheet reached 60º C in 5.2 minutes while the sample with the thickest coating took 11.7 minutes to attain this temperature. The sheet with the thickest coating required 19.35 minutes.
To further test the cooling effect of the material, a coated heat sink was applied to a microcomputing device. Chip temperature was reduced by up to 7° C compared with an uncoated heat sink when the device was operated at heavy workloads for 15 minutes. Thermal protection was also observed to be superior when the MOF coating described in Joule was applied relative to traditionally used phase change materials.
The researchers next plan to realize improvements in the coating’s heat dissipation capabilities and to reduce material costs.
