Temperature-adaptive metasurface radiative cooling device with excellent emittance and low solar absorptance for dynamic thermal regulation

Passive radiative cooling is a promising passive cooling technology that emits heat to deep space without energy consumption. Nevertheless, the persistent challenge of overcooling in static radiative techniques has raised concerns. Although a desirable solution is suggested based on vanadium dioxide (VO2) in the form of a Fabry–Perot (F–P) resonant cavity, the inherent contradiction between desired high emissivity (ε) and low solar absorptance (αsol) remains a notable limitation. Here, we employed a simple mask-filling technique to develop a temperature-adaptive metasurface radiative cooling device (ATMRD) for dynamic thermal regulation. Simulation and experimental results substantially evidenced that multiple localized polariton resonances were induced by the VO2 metasurface, significantly enhancing the thermal emittance of the ATMRDs. The engineered ATMRD achieved an amazing switch of the atmospheric window emittance from 0.13 to 0.85 when the surface temperature exceeds a pre-set transition temperature, accompanied by a commendable αsol of 27.71%. The mechanism of multiple localized polariton resonances is discussed in detail to understand the enhanced performance based on the investigation of the relationship between the metasurface structure and multiple localized polariton resonances. We demonstrate an efficient smart radiative technique achieved by a simple micro/nanoprocess and, most importantly, contribute a valuable reference for the design of radiative devices, which is crucial in various areas such as passive cooling, smart windows, multifunctional electromagnetic response, and space application technologies.