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Most 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. [ABSTRACT FROM AUTHOR]

Although personal thermal management (PTM) materials for daily routine environments are widely investigated, the exploration of multifunctional PTM materials with excellent feasibility in complex and outdoor scenarios is still in its infancy. Herein, inspired by the temperature regulation effect of the atmosphere, a novel design for fabricating solar‐thermal gradient reduced graphene oxide (RGO) aerogel‐based bilayer phase change composite (GRGC) featuring "energy regulation" and "energy inverse compensation" is proposed for self‐adaptive PTM applications. By integrating the solar‐thermal energy conversion ability of RGO, the heat regulation of the aerogel/octadecane bilayer structure with the unique gradient RGO framework inside, and the latent‐heat compensation of octadecane, the bilayer GRGC can serve as an efficient PTM device to mitigate drastic temperature changes of human skin in harsh environments. This multifunctional PTM device can not only keep a warm skin surface microclimate in a frigid environment of −5 °C via the synergistic effect of the solar‐thermal conversion, the aerogel thermal insulation, and the phase‐change latent heat release, but also provide efficient thermal buffering to prevent hyperthermia in hot environments through its phase‐change behavior and its thermal insulation. This gradient and bilayer design opens a new avenue for fabricating self‐adaptive PTM devices for applications in harsh environments. [ABSTRACT FROM AUTHOR]