Flexible W‐Doped VO 2 Multilayer Coatings for Spectrally Decoupled Structural Color and Temperature‐Adaptive Infrared Emission
Xiaofei Li, Changyuan Chen, Shaowen Cao, Jiasheng Li, Kaiyi Lyu, Hebing Hu, Yi Long, Yun MengABSTRACT
Thermally reconfigurable optical coatings that combine visible coloration with selective infrared emission are challenging because broadband low‐emissivity designs suppress both detectable radiation and radiative heat release. Here, we report a flexible, lithography‐free W‐doped VO 2 hybrid multilayer coating for spectrally decoupled visible coloration and temperature‐adaptive infrared emission. Visible coloration is governed by TiO 2 /SiO 2 thin‐film interference, whereas temperature‐dependent infrared regulation arises mainly from the optical transition of W‐doped VO 2 . The optimized coating maintains a low unweighted band‐averaged emissivity of ≤0.24 in the 3–5 µm mid‐wave infrared (MWIR) window in both thermal states, while its 8–20 µm emissivity increases from approximately 0.24 to 0.83 upon heating. Simulations show that TiO 2 ‐thickness‐based color tuning only weakly perturbs the infrared response and that the band‐resolved characteristics are retained under transverse‐electric (TE)‐polarized incidence up to 60°. The coating also preserves its characteristic infrared response after 100 machine‐controlled bending cycles at a radius of 10 mm. This flexible, lithography‐free architecture therefore enables largely decoupled visible appearance control, persistent MWIR suppression, and temperature‐activated long‐wavelength emission, providing a mechanically compliant platform for spectrally selective thermal emission and adaptive infrared photonics.