A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

The objective of the present invention is to provide a porous ultra-thin polymer film, and a method for producing said porous ultra-thin polymer film. The present invention provides a porous ultra-thin polymer film with a film thickness of 10 nm-1000 nm. In addition, the present invention provides a method for producing a porous ultra-thin polymer film, comprising the steps of: dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

An apparatus and method for transferring nanofiber structures (e.g., nanofiber films, nanofiber sheets, stacks of nanofiber grids, nanofiber films, nanofiber sheets, and combinations thereof) between various substrates are described. The techniques described use a soluble layer on a substrate that is subsequently dissolved, thus freeing the nanofiber structure from the substrate. This liquid phase techniques preserves the mechanical integrity and the purity of the nanofiber structures.

The present invention provides highly permeable and porous polybenzimidazole membranes, methods of making them, and their application as a high-performance membrane support for gas separation composite membranes. The polybenzimidazole membranes are bonded to a fabric substrate.

The present invention provides highly permeable and porous polybenzimidazole membranes. methods of making them, and their application as a high-performance membrane support for gas separation composite membranes. The polybenzimidazole membranes are bonded to a fabric substrate.

A hydrogen-selective membrane including a metal leaf applied to a substrate. A system and method for fabricating a hydrogen-selective membrane, including applying a metal leaf to a substrate, annealing the metal leaf, applying a hydrogen-permeable metal to the annealed metal leaf on the substrate, and annealing the hydrogen-permeable metal and the annealed metal leaf to give an alloy of the hydrogen-permeable metal and the metal leaf. A system and method for repairing a hydrogen-selective membrane having defects including applying a metal leaf to an external surface of membrane material of the hydrogen-selective membrane, annealing the metal leaf and metal of the membrane material to form an alloy of the metal leaf and the metal to repair the defects.

Technologies are generally described for composite membranes which may include a porous graphene layer in contact with a porous support substrate. In various examples, a surface of the porous support substrate may include at least one of: a thermo-formed polymer characterized by a glass transition temperature, a woven fibrous membrane, and/or a nonwoven fibrous membrane. Examples of the composite membranes permit the use of highly porous woven or nonwoven fibrous support membranes instead of intermediate porous membrane supports. In several examples, the composite membranes may include porous graphene layers directly laminated onto the fibrous membranes via the thermo-formed polymers. The described composite membranes may be useful for separations, for example, of gases, liquids and solutions.

Ultra-thin nanometer-sealer freestanding polymeric membranes and methods for producing ultra-thin nanometer-scale freestanding recast membranes and ultra-thin nanometer-scale freestanding cross-linked membranes with solid internal backbone are disclosed.

A method for making a nanoporous membrane is disclosed. The method provides a composite film comprising an atomically thin material layer and a polymer layer, and then bombarding the composite film with energetic particles to form a plurality of pores through at least the atomically thin material layer. The nanoporous membrane also has a atomically thin material layer with a plurality of apertures therethrough and a polymer film layer adjacent one side of the graphene layer. The polymer film layer has a plurality of enlarged pores therethrough, which are aligned with the plurality of apertures. All of the enlarged pores may be concentrically aligned with all the apertures. In one embodiment the atomically thin material layer is graphene.

An array of discrete nanofiber films that are physically separated from one another are described. Techniques for forming the nanofiber film array are also described. Techniques for forming these structures include placing a suspension of nanofibers and/or nanoparticles on a patterned substrate. A pressure differential is applied, drawing the solvent of the suspension through holes in a mask. The nanofibers collect on an impermeable layer on the mask in a pattern corresponding to the negative features (grooves, holes, trenches) of the mask as the solvent is flowed through the holes.