Composite material for passive radiative cooling

Abstract

A composite material for passive radiative cooling including a base layer, and at least one emissive layer located adjacent to a surface of the base layer, wherein the at least one emissive layer is affixed to the surface of the base layer via a binding agent.

What is claimed is: 
     
         1 . A method of providing a composite material for passive radiative cooling to a surface, said method comprising:
 obtaining access to an object to be cooled through passive radiative cooling, said object having a surface;   applying to said surface a liquid suspension of microparticles in a liquid binding agent; and   curing said binding agent so as to form a thermally-emissive layer on said surface, whereby said thermally-emissive layer is affixed to said surface via said binding agent.   
     
     
         2 . The method of  claim 1 , wherein said object comprises a base layer to which said liquid suspension is applied, said base layer comprising a reflective substrate. 
     
     
         3 . The method of  claim 2 , wherein said reflective substrate is composed of at least one of aluminum, silver, glass, polyurethane, nylon, and polyethylene fibers. 
     
     
         4 . The method of  claim 2 , wherein said reflective substrate comprises paint. 
     
     
         5 . The method of  claim 1 , wherein said binding agent is composed of a polymer material. 
     
     
         6 . The method of  claim 1 , wherein said binding agent is transparent. 
     
     
         7 . The method of  claim 1 , wherein said binding agent includes a characteristic thickness less than or equal to approximately 50 μm. 
     
     
         8 . The method of  claim 1 , wherein said at least one emissive layer is composed of silica material. 
     
     
         9 . The method of  claim 1 , wherein said at least one emissive layer comprises a plurality of microparticles. 
     
     
         10 . The method of  claim 9 , wherein each of said plurality of microparticles is composed of silica material. 
     
     
         11 . The method of  claim 9 , wherein each of said plurality of microparticles includes a characteristic dimension between about 5 to about 50 μm. 
     
     
         12 . The method of  claim 9 , wherein each of said plurality of microparticles includes a characteristic dimension less than or equal to 30 μm. 
     
     
         13 . The method of  claim 1 , wherein said liquid suspension is applied in the form of a spray. 
     
     
         14 . A method of providing a composite material for passive radiative cooling to a surface, said method comprising:
 obtaining access to an object to be cooled through passive radiative cooling, said object having a base layer;   applying to said base layer a liquid suspension of microparticles in a liquid binding agent to said base layer, and   curing said binding agent so as to form at least one thermally-emissive layer located adjacent to a surface of the base layer, wherein the surface of the base layer comprises a reflective substrate comprising an adhesive layer, and wherein the at least one emissive layer is affixed to the base layer via the adhesive layer of the base layer.   
     
     
         15 . The method of  claim 14 , wherein said reflective substrate comprises paint. 
     
     
         16 . The method of  claim 14 , wherein said reflective substrate comprises glue. 
     
     
         17 . The method of  claim 14 , wherein said at least one emissive layer comprises a silica material. 
     
     
         18 . The method of  claim 14 , wherein said at least one emissive layer comprises a plurality of microparticles. 
     
     
         19 . The method of  claim 18 , wherein each of said plurality of microparticles includes a characteristic dimension between about 5 to about 50 μm. 
     
     
         20 . The method of  claim 18 , wherein each of said plurality of microparticles includes a characteristic dimension less than or equal to 30 μm. 
     
     
         21 . The method of  claim 14 , wherein said liquid suspension is applied in the form of a spray.