Abstract: Structures comprising a first sheet of perforated two-dimensional material and a first plurality of spacer elements disposed between a surface of the first sheet of perforated two-dimensional material and at least one of a surface of a structural substrate and a surface of a second sheet of perforated two-dimensional material are disclosed, as well as related methods. The structures may further comprise a structural substrate, a second plurality of spacer elements, additional sheets of perforated two-dimensional material in direct contact with the first and/or said second sheet of perforated two-dimensional material and/or relief features in the surface of the structural substrate.

Abstract: Permeable materials, such as perforated grapheme and other two-dimensional materials, can be used in filtration applications. However, there are presently no effective testing apparatuses or techniques to determine if a particular permeable material or other membrane is suitable for a given filtration process. Determining concentration polarization in a cross-flow filtration configuration can be especially difficult. Apparatuses disclosed herein for evaluating permeable materials, particularly perforated two-dimensional materials, in filtration membranes can include a flow channel, such as a lateral flow channel, in fluid communication with a membrane containing a permeable material, a porous substrate supporting the permeable material, and a plurality of fluid collection ports disposed laterally with respect to the flow channel. The fluid collection ports are disposed on the side of the permeable material that is opposite the flow channel. Other membranes can also be evaluated with the described apparatuses.

Abstract: Composite membranes of the present disclosure can include a porous supporting substrate having a coating thereon, and one or more two-dimensional materials disposed on the coating. The coating material can include SiO2 or various precursors thereof, which can be disposed on the porous supporting substrate by various deposition techniques. Methods for forming a composite membrane can include providing a porous supporting substrate, applying a coating on the porous supporting substrate, and disposing one or more two-dimensional materials on the coating.