Metamaterials-Enhanced Passive Radiative Cooling Panel

摘要

A low-cost passive radiative cooling panel includes an emitter layer disposed under an upper reflective layer, where the emitter layer includes metamaterial nanostructures (e.g., tapered nanopores) configured to dissipate heat in the form of radiant energy that is transmitted through the reflective layer into cold near-space. In an embodiment the emitter layer includes ultra-black material configured to emit, with an emissivity close to unity, radiant energy having wavelengths/frequencies that fall within known atmospheric transparency windows (e.g., 8-13 μm or 16-28 μm). In a practical embodiment the emitter layer is formed using a modified Anodic Aluminum Oxide (AAO) self-assembly technique followed by electroless plating that forms metal-plated tapered nanopores. The reflective layer includes a distributed Bragg reflector configured to reflect at least 94% of incident solar light while passing the emitted radiant energy, and in some embodiments is implemented using a low-cost, commercially available solar mirror film.

主权项

1. 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; and 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.