Radiative cooling device and method of manufacturing the same

A method of manufacturing a radiative cooling device, the method comprising:

• forming a reflective layer for reflecting sunlight having wavelengths corresponding to ultraviolet, visible, and near-infrared regions on a substrate;
• and
• forming, on the reflective layer, a radiative cooling layer for absorbing sunlight having a wavelength corresponding to a mid-infrared region and emitting the sunlight as heat,
• wherein forming the radiative cooling layer comprises forming, on the reflective layer, a first radiation layer comprising an uneven pattern and
• forming, on the first radiation layer, a second radiation layer having a refractive index different from that of the first radiation layer,
• wherein the radiative cooling layer comprises a mid-infrared light absorption layer disposed on the reflective layer and responsible for absorbing a first sunlight having a wavelength corresponding to a mid-infrared region and emitting the first sunlight as heat,
• wherein a coating layer is disposed on the mid-infrared light absorption layer and comprises a first coating layer and a second coating layer having different refractive indexes with respect to a second sunlight having a wavelength corresponding to a visible region, and
• wherein the first coating layer has a greater refractive index than the second coating layer with respect to the second sunlight and a difference between the refractive index of the first coating layer and the refractive index of the second coating layer is 0.7 to 2.

A white radiative cooling device, comprising:

• a substrate;
• and
• a white radiative cooling layer disposed on the substrate, wherein, in the white radiative cooling layer, fine particles comprising a metal oxide or a polymer that reflects and scatters a first sunlight having a wavelength corresponding to a visible region are embedded in a polymer matrix that absorbs a second sunlight having a wavelength corresponding to a mid-infrared region and emits the second sunlight as heat,
• wherein the white radiative cooling layer absorbs the second sunlight and emits the second sunlight as heat while reflecting and scattering the first sunlight, and
• wherein, in the white radiative cooling layer, fluorescent particles for emitting fluorescence are embedded in the polymer matrix.