Metamaterials-enhanced passive radiative cooling panel

A passive radiative cooling panel comprising:

• an emitter layer including a plurality of metamaterial nanostructures configured to dissipate heat by generating radiant energy that is emitted from a surface of the emitter layer, wherein the metamaterial nanostructures are further configured such that at least a portion of said generated radiant energy having wavelengths corresponding to one or more atmospheric transparency windows is emitted with an emissivity of at least 0.998;
• an upper layer having a downward-facing surface facing the surface of the emitter layer and an opposing upward-facing surface, wherein the upper layer is configured to reflect incident solar radiation directed onto the upward-facing surface, and configured to transmit at least said portion of said radiant energy emitted from the emitter layer, whereby said portion of said radiant energy is transmitted through the upward-facing surface of the upper layer;
• and
• wherein the emitter layer comprises a base material layer including an array of said metamaterial nanostructures, the array of metamaterial nanostructures comprises an array of tapered nanopores defined into the base material layer, a nominal width of each said tapered nanopore is equal to or less than 1 micron.