Affiliation:
1. State Key Laboratory of Organic‐Inorganic Composites College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China
2. Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical Technology Beijing 100029 China
3. Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong 999077 China
Abstract
AbstractMost low infrared emissivity coatings for anti‐infrared reconnaissance are merely suitable for targets warmer than their surroundings, and their flexibility and wearability are unsatisfactory for dynamic stealth applications. Herein, a spectral‐selective and adjustable patterned polydimethylsiloxane/MXene/nanoporous polytetrafluoroethylene metafabric with an asymmetric structure is designed, which achieves spectral selectivity of reflection/emission in mid‐infrared wavebands and synchronous reflection/absorption of solar light, integrating “shielded infrared stealth” and “compensatory thermal camouflage” in temperature‐change scenarios. By synergizing the low infrared emissivity of MXene and the effective heat‐transfer suppression of the patterned polydimethylsiloxane, the metafabric obtains an infrared emissivity of as low as ≈28% and minimizes the radiative temperature difference between a target of 36 °C and its low‐temperature surroundings even to 2.5 °C. Conversely, the metafabric adaptively unitizes its surface infrared signature with its high‐temperature background via the thermal energy compensation supplied by the solar‐thermal/electrothermal conversion of MXene and the powerful radiation emission of the outer polydimethylsiloxane. Besides, the metafabric creates a comfortable skin‐interface microclimate by the high solar‐light reflection of the nanoporous polytetrafluoroethylene and exhibits satisfactory electromagnetic interference shielding performances, mechanical flexibility, self‐cleaning, and antioxidation. This work provides a new strategy for designing multifunctional thermal camouflage materials for counter‐reconnaissance in changeable surroundings.
Funder
Natural Science Foundation of Beijing Municipality
Fundamental Research Funds for the Central Universities of Beijing University of Chemical Technology
National Natural Science Foundation of China