Radiative thermal coats for passive temperature management

Radiative thermal management has advantages in precision electronic instruments owing to zero-energy consumption and high integration convenience. The possibility to acquire high-performance thermal stability through engineering the surface emissivity of object has been investigated. Herein, developing a smart coat was reported that could passively maintain the temperature of objects (silicon chips) in a predefined thermal window to avoid overheating or overcooling in vacuum. The technique implements using a multilayer structure incorporating a 30 nm thick VO2 phase-change medium having a 300% modulation depth for emissivity under varying temperatures. In the experiment, a 1.78 μm thick smart coat could raise the temperature stability of a regular coat by ∼2.0 times. The potential of the work remains in thermal radiation for smart temperature management especially in space applications.