Since the ancient Egyptians first filtered water through sand, man has used screens and filters for everything from large-scale industrial processes to brewing beverages to delicate medical procedures.
Today, filtration and separation process are all around us, in almost every industry in some form, and the need for improved performance and efficiency is greater than ever. New technologies are opening new frontiers.
Lockheed Martin is making revolutionary breakthroughs with its graphene composite membrane technology. The active layer of our membranes is an atomically thin layer of perforated graphene, which puts the theoretical limits of membrane performance within reach. Graphene membranes feature many of the benefits of standard track etched separation membranes, but at several times their permeability permeability because of graphene’s thinness. No membrane can be thinner than an atom. But can something so thin be practical in the real world? Yes. Our membranes can withstand 100’s of psi of trans-membrane pressure, can tolerate high radii of curvature, are highly flexible, and device fabrication processes can be performed by skilled technicians using hand tools outside of a clean room environment. Also, our membranes are probably more affordable than you think.
Perforene is expanding out of the lab and partnering with outside organizations on real-world applications. If you are interested in learning more or would like to explore opportunities for using our graphene membranes, please contact Mike Hiltabidle.
Building on almost 200 patented and patent pending technologies, our graphene membrane technology has a wide-range of applications in such areas as molecular sieving, reverse osmosis, forward osmosis, chemical separations, gas-phase separations, nano- and ultra-filtration, gas-phase separations, laboratory separations, dialysis, hemofiltration, water sterilization, sensors, protein separation, viral clearance, and other medical uses.
Three key features set Lockheed Martin’s membranes apart: Substrate diversity, high quality, and large area perforation.
Our membranes are graphene composite membranes, consist of a perforated graphene layer combined with a highly porous substrate. We can tailor the properties of the substrate via functionalization and other means to give the resulting graphene composite membrane a wide variety of properties.
We have developed a unique unsupported transfer technology with allows us to transfer high quality graphene layers to a wide variety of substrates at very low defect rates. We are adding new substrates all the time.
Track Etched Polymide
Track Etched Polycarbonate
Microporous SiN Substrate
Several Micron Span
PVDF Microfiltration Membrane
Nanoporous SiN Substrate
Carbon Nanomaterial Membrane
Microporous SiN Substrate
Most of the graphene membrane field uses highly planar substrates such as track etched membranes. We have expanded our capability to other substrate topologies.
Other groups around the world have published on large area graphene and roll-to-roll processes. How perfect is that graphene? Graphene for separation membranes requires an extremely low defect rate at the nanoscale. Even nanoscopic defects can be leaks for some separation applications. We have achieved the degree of quality to make graphene-based separation membranes a reality at functional scale. Because of this quality, unperforated versions of our membrane can make effective impermeable barriers.
Large Area Perforation
Lockheed Martin has developed a technology capable of large area, highly controlled, graphene perforation. Not limited to drilling individual pores on a scale too small to be practical, our perforation technology is a key aspect making our membranes practical for real world uses. We typically perforate in the range of single digit nanometers up to 100 nanometers. Our membranes are capable of very high permeability even with pores in this size range primarily because of graphene’s atomic thinness.
Today, individual devices can be as large as several cm^2. Larger membranes areas are possible using techniques to tile smaller devices together. There is a clear path to further scale-up for the right applications.
Other Properties of Graphene Membranes
Impermeable even to helium when not perforated
One atom thick, but handleable (cite MIT paper)
Perforatable on the nanoscale
Can integrate with a variety of substrates
Layered, part of a composite