Microsphere-based coatings for radioactive cooling under direct sunlight
The present prevention provides a surface coating for cooling a surface by light scattering comprising a plurality of successive layers, each of the layers may be comprised of a plurality of spheres arranged to form a structure comprised of packed spheres. Each layer may have a different arrangement of packed spheres to create to a different light scattering property in each of the layers. The coating of the structures may also be formed by randomly packed spheres and the spheres may have a uniform diameter.
1. A tiered structure for cooling a surface of a substrate by light scattering comprising:
a plurality of successive layers;
each of said layers comprised of a plurality of spheres arranged to form a structure comprised of randomly packed spheres;
each structure of each layer has a different arrangement of randomly packed spheres to create to a different light scattering property in each of said layers; and
wherein said structures are formed by randomly packed spheres and said spheres have a uniform diameter.
2. The tiered structure of claim 1 wherein said tiered structures emits light in a range of 8-13 microns.
3. The tiered structure of claim 2 wherein said tiered structure also emits light in a range of 18-30 microns.
4. The tiered structure of claim 1 wherein each of said layers has a fixed periodicity and the periodicity of each layer is different.
5. The tiered structure of claim 1 further including multilayers of spheres with a predetermined degree of randomness.
6. The tiered structure of claim 1 wherein each of said layers is made of a monolayer of microspheres with a predetermined degree of randomness.
7. The tiered structure of claim 1 wherein each of said layers has a sphere filling fraction of less than 55%.
8. The tiered structure of claim 1 wherein each of said layers has a sphere filling fraction between 20-45% and said spheres have a diameter between 0.4 and 1 micron.
9. A tiered structure for cooling a surface of a substrate by light scattering comprising:
a plurality of successive layers;
each of said layers comprised of a plurality of spheres arranged to form a structure comprised of randomly packed spheres;
each structure of each layer has a different arrangement of randomly packed spheres to create to a different light scattering property in each of said layers;
said layers are comprised of lateral periodic structures and non-periodic structures; and
said periodic layers are ordered structures and said non-periodic structures are random structures.
10. A tiered structure for cooling a surface of a substrate by light scattering comprising:
a plurality of successive layers;
each of said layers comprised of a plurality of spheres arranged to form a structure comprised of randomly packed spheres;
each structure of each layer has a different arrangement of randomly packed spheres to create to a different light scattering property in each of said layers;
each of said layers has a fixed periodicity and the periodicity of each layer is different; and
each of said layers has spheres joined into fibrillar networks and said fibrillar networks of each layer have different periodicities and orientations.