Abstract: The present disclosure is directed to methods for preparing nanoparticle monolayers on a sub-phase by controlling the spreading rate of the nanoparticles. The nanoparticles are first prepared in a nanoparticle solution at a predetermined concentration with a solvent. The sub-phase solution is prepared to have a density and viscosity compatible with the desired spreading rate. Additives, such as glycerol, are used to alter the density of the sub-phase solution. A volume of nanoparticle solution is deposited on the surface of the sub-phase solution and allowed to spread in a controlled manner on the unconstrained surface, forming a uniform nanoparticle monolayer. A substrate is then placed in contact with the nanoparticle monolayer to form a uniform nanoparticle coating on the surface of the substrate.

Abstract: The present disclosure generally pertains to methods of preparing a well-ordered nanoparticle coating on a substrate. A nanoparticle solution having nanoparticles in a solvent is deposited on a sub-phase of a denser, immiscible liquid. A constrained area on the top surface of the sub-phase is provided, where nanoparticle solution spreading is physically limited and the nanoparticles spontaneously form a uniformly ordered monolayer on the sub-phase within the constrained area. Notably, no compression of the nanoparticle film occurs after the spreading phase in order to form the monolayer. After the monolayer is formed, a substrate is placed into contact with the monolayer and coated with a well-ordered nanoparticle coating.

Abstract: The present disclosure is directed to methods for preparing nanoparticle monolayers on a sub-phase by controlling the spreading rate of the nanoparticles. The nanoparticles are first prepared in a nanoparticle solution at a predetermined concentration with a solvent. The sub-phase solution is prepared to have a density and viscosity compatible with the desired spreading rate. Additives, such as glycerol, are used to alter the density of the sub-phase solution. A volume of nanoparticle solution is deposited on the surface of the sub-phase solution and allowed to spread in a controlled manner on the unconstrained surface, forming a uniform nanoparticle monolayer. A substrate is then placed in contact with the nanoparticle monolayer to form a uniform nanoparticle coating on the surface of the substrate.