▎ 摘　　要

NOVELTY - A device for controlling emissivity of a surface comprises active layer comprising 5-500 atomic layers of graphene, where active layer has 1st and 2nd surfaces; substrate that comprises fibers and, absorbed into the fibers of the substrate, an ionic liquid or liquid electrolyte, where substrate has 1st and 2nd surfaces in which 2nd surface of active layer is in contact with 1st surface of substrate; conductor that is in contact with 2nd surface of the substrate; and unit for applying a controllably variable electrical potential between the conductor and the active layer. USE - A device for controlling emissivity of a surface (claimed). ADVANTAGE - When a voltage is applied between the conductive layer and the active layer, ions from the ionic liquid/liquid electrolyte intercalate between the graphene layers of the active layer. At 0 V, multilayer graphene has high infrared absorption which leads to high emissivity. When a sufficient voltage difference is applied ( greater than or equal to 2.5 V), the intercalation of the ions from the ionic liquid into the graphene layers enhances the optical conductivity of the graphene and suppresses the emissivity. The fiber substrate thus serves not only as a mechanical support, but also as an electrical separator, and ionic medium. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) method of varying the emissivity of the 1st surface of the active layer of the device which involves varying the electrical potential that is applied between the conductive layer and the active layer; and (2) making the device which involves (i) affixing the 2nd surface of the active layer with the 1st surface of the substrate, (ii) affixing the conductor to the 2nd surface with the substrate, and (iii) diffusing ionic liquid into the substrate.