Method of forming metal nanostructure-based structure
Various embodiments of the present disclosure are directed to structures comprising a nanostructure layer that includes a plurality of transparent conductors and coating layer formed on a surface thereof. In some embodiments, the coating layer includes one or more conductive plugs having outer and inner surfaces. The inner surface the plug is placed in electrical communication with the nanostructure layer and the outer surface forms conductive surface contacts proximate an outer surface of the coating layer. In some embodiments, the structure includes a polarizer and is used as a shielding layer in flat panel electrochromic displays, such as liquid crystal displays, touch panels, and the like.
1. A method of forming a metal nanostructure-based structure, the method comprising:
providing a nanostructure layer having a surface, the nanostructure layer comprising a non-volatile component and a plurality of nanostructures randomly distributed in the non-volatile component, wherein the nanostructures are networking and percolative, a number of the nanostructures makes the nanostructure layer reach at least a percolation threshold of the nanostructure layer, and the nanostructure layer is electrically conductive;
forming an overcoat solution by mixing a coating material with a plurality of removable particles randomly distributed therein;
coating the overcoat solution, including the coating material and the removable particles simultaneously, on the surface of the nanostructure layer in a liquid form to form a coating layer, wherein the coating layer has opposite first and second surfaces;
hardening the coating material;
dissolving the removable particles in a solution to form a plurality of voids in the coating layer and to expose at least one of the plurality of nanostructures, after the coating material is hardened, wherein the voids extend from the first surface to the second surface; and
at least partially filling the voids with a conductive material.
2. The method of claim 1 , wherein the removable particles comprise a water-soluble polymer.
3. The method of claim 1 , wherein forming the voids in the coating layer comprises rinsing the coating layer with water to dissolve the removable particles.
4. The method of claim 1 , wherein a particle size of the removable particles is selected to be greater than or equal to a thickness of the coating layer upon the coating material being hardened.
5. The method of claim 1 , wherein the removable particles comprise hydroxypropyl methyl cellulose, carboxymethyl cellulose or poly acrylic acid.
6. The method of claim 1 , wherein the removable particles are in the form of solid particles when the coating material and the removable particles are mixed.
7. The method of claim 6 , further comprising:
controlling the particle size of the removable particles by spray drying, grinding, or milling, before the coating material and the removable particles are mixed.
8. The method of claim 1 , wherein the removable particles are in the form of an aqueous polymer solution when the coating material and the removable particles are mixed.
9. The method of claim 8 , wherein the aqueous polymer solution is formed into an inverse emulsion or inverse suspension through mixing and addition of surfactant.
10. The method of claim 9 , wherein the removable particles are solidified during the step of hardening the coating material.
11. The method of claim 9 , wherein the removable particles are sub-micron to micron diameter aqueous droplets suspended in the coating material, and the coating material is non-aqueous, when the coating material and the removable particles are mixed.
12. The method of claim 1 , wherein the removable particles are sucrose.
13. The method of claim 1 , wherein the coating layer material is hardened by UV curing, thermal curing, or drying.