•Smart chemistry quickly makes toxic nerve gases nontoxic
•Material’s features bring it closer to practical use in the field
•New approach is scalable and economical
•Seeks to replace current technology of activated carbon
This new composite material one day could be integrated into protective suits and face masks for use by people facing hazardous conditions, such as chemical warfare.
The material, a zirconium-based metal-organic framework (MOF), degrades in minutes some of the most toxic chemical agents known to mankind: VX and soman (GD), a more toxic relative of sarin.
“With the correct chemistry, we can render toxic gases nontoxic,” said Omar K. Farha, associate professor of chemistry in the Weinberg College of Arts and Sciences, who led the research. “The action takes place at the nanolevel.”
The authors write that their work represents, to the best of their knowledge, the first example of the use of MOF composites for the efficient catalytic hydrolysis of nerve agent simulants without using liquid water and toxic volatile bases — a major advantage.
The new composite material integrates MOFs and non-volatile polymeric bases onto textile fibers.
The researchers found the MOF-coated textiles efficiently detoxify nerve agents under battlefield-relevant conditions using the gaseous water in the air. They also found the material stands up over a long period of time to degrading conditions, such as sweat, atmospheric carbon dioxide and pollutants.
These features bring the promising material closer to practical use in the field.
“MOFs can capture, store and destroy a lot of the nasty material, making them very attractive for defense-related applications,” said Farha, a member of the International Institute for Nanotechnology.
What Are MOF’s?
MOFs are well-ordered, lattice-like crystals. The nodes of the lattices are metals, and organic molecules connect the nodes. Within their very roomy pores, MOFs can effectively capture gases and vapors, such as nerve agents.
It is these roomy pores that also can pull enough water from the humidity in the air to drive the chemical reaction in which water is used to break down the bonds of the nerve agent.
The approach developed at Northwestern seeks to replace the technology currently in use: activated carbon and metal-oxide blends, which are slower to react to nerve agents. Because the MOFs are built from simple components, the new approach is scalable and economical.
The research was supported by the Defense Threat Reduction Agency (grants HDTRA1-18-1-0003 and CB3934) and the National Science Foundation Graduate Research Fellowship (grant DGE-1842165).
The title of the paper is “Integration of Metal–Organic Frameworks on Protective Layers for Destruction of Nerve Agents under Relevant Conditions.” The first authors are Zhijie Chen and Kaikai Ma, postdoctoral fellows in Farha’s research group.
Source contact: Omar Farha at email@example.com
Copyright © Northwestern University
Carbon nanotube film produces aerospace-grade composites with no need for huge ovens or autoclaves.
A modern airplane’s fuselage is made from multiple sheets of different composite materials, like so many layers in a phyllo-dough pastry. Once these layers are stacked and molded into the shape of a fuselage, the structures are wheeled into warehouse-sized ovens and autoclaves, where the layers fuse together to form a resilient, aerodynamic shell.
Now MIT engineers have developed a method to produce aerospace-grade composites without the enormous ovens and pressure vessels. The technique may help to speed up the manufacturing of airplanes and other large, high-performance composite structures, such as blades for wind turbines.
The researchers detail their new method in a paper published today in the journal Advanced Materials Interfaces.
“If you’re making a primary structure like a fuselage or wing, you need to build a pressure vessel, or autoclave, the size of a two- or three-story building, which itself requires time and money to pressurize,” says Brian Wardle, professor of aeronautics and astronautics at MIT. “These things are massive pieces of infrastructure. Now we can make primary structure materials without autoclave pressure, so we can get rid of all that infrastructure.”
Wardle’s co-authors on the paper are lead author and MIT postdoc Jeonyoon Lee, and Seth Kessler of Metis Design Corporation, an aerospace structural health monitoring company based in Boston.
Out of the oven, into a blanket
In 2015, Lee led the team, along with another member of Wardle’s lab, in creating a method to make aerospace-grade composites without requiring an oven to fuse the materials together. Instead of placing layers of material inside an oven to cure, the researchers essentially wrapped them in an ultrathin film of carbon nanotubes (CNTs). When they applied an electric current to the film, the CNTs, like a nanoscale electric blanket, quickly generated heat, causing the materials within to cure and fuse together.
With this out-of-oven, or OoO, technique, the team was able to produce composites as strong as the materials made in conventional airplane manufacturing ovens, using only 1 percent of the energy.
The researchers next looked for ways to make high-performance composites without the use of large, high-pressure autoclaves — building-sized vessels that generate high enough pressures to press materials together, squeezing out any voids, or air pockets, at their interface.
“There’s microscopic surface roughness on each ply of a material, and when you put two plys together, air gets trapped between the rough areas, which is the primary source of voids and weakness in a composite,” Wardle says. “An autoclave can push those voids to the edges and get rid of them.”
Researchers including Wardle’s group have explored “out-of-autoclave,” or OoA, techniques to manufacture composites without using the huge machines. But most of these techniques have produced composites where nearly 1 percent of the material contains voids, which can compromise a material’s strength and lifetime. In comparison, aerospace-grade composites made in autoclaves are of such high quality that any voids they contain are neglible and not easily measured.
“The problem with these OoA approaches is also that the materials have been specially formulated, and none are qualified for primary structures such as wings and fuselages,” Wardle says. “They’re making some inroads in secondary structures, such as flaps and doors, but they still get voids.”
Part of Wardle’s work focuses on developing nanoporous networks — ultrathin films made from aligned, microscopic material such as carbon nanotubes, that can be engineered with exceptional properties, including color, strength, and electrical capacity. The researchers wondered whether these nanoporous films could be used in place of giant autoclaves to squeeze out voids between two material layers, as unlikely as that may seem.
A thin film of carbon nanotubes is somewhat like a dense forest of trees, and the spaces between the trees can function like thin nanoscale tubes, or capillaries. A capillary such as a straw can generate pressure based on its geometry and its surface energy, or the material’s ability to attract liquids or other materials.
The researchers proposed that if a thin film of carbon nanotubes were sandwiched between two materials, then, as the materials were heated and softened, the capillaries between the carbon nanotubes should have a surface energy and geometry such that they would draw the materials in toward each other, rather than leaving a void between them. Lee calculated that the capillary pressure should be larger than the pressure applied by the autoclaves.
The researchers tested their idea in the lab by growing films of vertically aligned carbon nanotubes using a technique they previously developed, then laying the films between layers of materials that are typically used in the autoclave-based manufacturing of primary aircraft structures. They wrapped the layers in a second film of carbon nanotubes, which they applied an electric current to to heat it up. They observed that as the materials heated and softened in response, they were pulled into the capillaries of the intermediate CNT film.
The resulting composite lacked voids, similar to aerospace-grade composites that are produced in an autoclave. The researchers subjected the composites to strength tests, attempting to push the layers apart, the idea being that voids, if present, would allow the layers to separate more easily.
“In these tests, we found that our out-of-autoclave composite was just as strong as the gold-standard autoclave process composite used for primary aerospace structures,” Wardle says.
The team will next look for ways to scale up the pressure-generating CNT film. In their experiments, they worked with samples measuring several centimeters wide — large enough to demonstrate that nanoporous networks can pressurize materials and prevent voids from forming. To make this process viable for manufacturing entire wings and fuselages, researchers will have to find ways to manufacture CNT and other nanoporous films at a much larger scale.
“There are ways to make really large blankets of this stuff, and there’s continuous production of sheets, yarns, and rolls of material that can be incorporated in the process,” Wardle says.
He plans also to explore different formulations of nanoporous films, engineering capillaries of varying surface energies and geometries, to be able to pressurize and bond other high-performance materials.
“Now we have this new material solution that can provide on-demand pressure where you need it,” Wardle says. “Beyond airplanes, most of the composite production in the world is composite pipes, for water, gas, oil, all the things that go in and out of our lives. This could make making all those things, without the oven and autoclave infrastructure.”
This research was supported, in part, by Airbus, ANSYS, Embraer, Lockheed Martin, Saab AB, Saertex, and Teijin Carbon America through MIT’s Nano-Engineered Composite aerospace Structures (NECST) Consortium.
With enhanced properties such as greater strength, lighter weight, increased electrical conductivity and chemical reactivity, nanomaterials (NMs) are widely used in areas like ICT, energy and medicine. For example, nanotubes, nanorods and nanowires with different size, structure and chemical composition have been successfully synthesised for various applications in mechanical, electromechanical, electric and optoelectronic devices.
Defined as materials with at least one external dimension sized between 1 nm and 100 nm, or with internal structures measuring 100 nm or less, NMs play a crucial role in the next generation of mobile phones, computer chips, batteries, autonomous devices and robotics. Therefore, it’s important to know which set of structural and electrical properties for such materials gives the best performance for a particular application. Scientists and engineers are increasingly focusing on developing NMs that are highly energy efficient. But, the tinier NMs become, the harder it gets for them to manage the heat generated during the processing of information.
The EU-funded ENGIMA project has been addressing these issues. It was set up to explore “the structure-property relationships in the elaborated nanostructured multifunctional materials,” as noted on the project website. “It [ENGIMA] focuses on how to redistribute electricity efficiently at miniscule scales, harnessing nanotechnology breakthroughs that are opening up new possibilities and applications thought impossible until just a few years ago,” according to an article on the European Commission website.
As stated in the article, researchers involved with the project “developed a permanent static ‘negative capacitor,’ a device thought impossible until about a decade ago. Previously proposed designs for negative capacitors worked on a temporary, transient basis but the ENGIMA-developed negative capacitor is the first to operate as a steady-state reversible device.” Capacitance refers to a measure of the amount of electric potential energy stored or separated for a given electric potential.
The same article adds: “The proposed approach harnesses properties of ferroelectric materials, which possess spontaneous polarization that can be reversed by an external electric field. Increasing the charge on the positive capacitor increases the voltage. The reverse occurs with the negative capacitor—its voltage drops as the charge increases.” The combination of the two capacitors “enables electricity to be distributed to regions of the circuit requiring higher voltage while the entire circuit operates at a lower voltage.” This is a crucial development because it helps tackle overheating problems affecting the performance of conventional computing circuits. “Building on this research, we are developing a practical platform for implementing ultra-low-power devices for information processing,” says ENGIMA lead researcher Igor Lukyanchuk.
Increasing the performance of processors means smartphones and various other electronic systems will become more energy efficient. Scheduled to end in late 2021, the ENGIMA (Engineering of Nanostructures with Giant Magneto-Piezoelectric and Multicaloric Functionalities) project will also help scientists design new nanostructures for future photovoltaic materials. “The results emerging from ENGIMA promise to open significant new opportunities and possibilities for high-tech industries, particularly in addressing current energy consumption and harvesting issues, with applications across many fields,” the European Commission article says.
Scientists have developed a platform for assembling nanosized material components, or “nano-objects,” of very different types—inorganic or organic—into desired 3-D structures. Though self-assembly (SA) has successfully been used to organize nanomaterials of several kinds, the process has been extremely system-specific, generating different structures based on the intrinsic properties of the materials. As reported in a paper published today in Nature Materials, their new DNA-programmable nanofabrication platform can be applied to organize a variety of 3-D materials in the same prescribed ways at the nanoscale (billionths of a meter), where unique optical, chemical, and other properties emerge.
“One of the major reasons why SA is not a technique of choice for practical applications is that the same SA process cannot be applied across a broad range of materials to create identical 3-D ordered arrays from different nanocomponents,” explained corresponding author Oleg Gang, leader of the Soft and Bio Nanomaterials Group at the Center for Functional Nanomaterials (CFN)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory—and a professor of Chemical Engineering and of Applied Physics and Materials Science at Columbia Engineering. “Here, we decoupled the SA process from material properties by designing rigid polyhedral DNA frames that can encapsulate various inorganic or organic nano-objects, including metals, semiconductors, and even proteins and enzymes.”
The scientists engineered synthetic DNA frames in the shape of a cube, octahedron, and tetrahedron. Inside the frames are DNA “arms” that only nano-objects with the complementary DNA sequence can bind to. These material voxels—the integration of the DNA frame and nano-object—are the building blocks from which macro-scale 3-D structures can be made. The frames connect to each other regardless of what kind of nano-object is inside (or not) according to the complementary sequences they are encoded with at their vertices. Depending on their shape, frames have a different number of vertices and thus form entirely different structures. Any nano-objects hosted inside the frames take on that specific frame structure.
To demonstrate their assembly approach, the scientists selected metallic (gold) and semiconducting (cadmium selenide) nanoparticles and a bacterial protein (streptavidin) as the inorganic and organic nano-objects to be placed inside the DNA frames. First, they confirmed the integrity of the DNA frames and formation of material voxels by imaging with electron microscopes at the CFN Electron Microscopy Facility and the Van Andel Institute, which has a suite of instruments that operate at cryogenic temperatures for biological samples. They then probed the 3-D lattice structures at the Coherent Hard X-ray Scattering and Complex Materials Scattering beamlines of the National Synchrotron Light Source II (NSLS-II)—another DOE Office of Science User Facility at Brookhaven Lab. Columbia Engineering Bykhovsky Professor of Chemical Engineering Sanat Kumar and his group performed computational modeling revealing that the experimentally observed lattice structures (based on the X-ray scattering patterns) were the most thermodynamically stable ones that the material voxels could form.
“These material voxels allow us to begin to use ideas derived from atoms (and molecules) and the crystals that they form, and port this vast knowledge and database to systems of interest at the nanoscale,” explained Kumar.
Gang’s students at Columbia then demonstrated how the assembly platform could be used to drive the organization of two different kinds of materials with chemical and optical functions. In one case, they co-assembled two enzymes, creating 3-D arrays with a high packing density. Though the enzymes remained chemically unchanged, they showed about a fourfold increase in enzymatic activity. These “nanoreactors” could be used to manipulate cascade reactions and enable the fabrication of chemically active materials. For the optical material demonstration, they mixed two different colors of quantum dots—tiny nanocrystals that are being used to make television displays with high color saturation and brightness. Images captured with a fluorescence microscope showed that the formed lattice maintained color purity below the diffraction limit (wavelength) of light; this property could allow for significant resolution improvement in various display and optical communication technologies.
“We need to rethink how materials can be formed and how they function,” said Gang. “Material redesign may not be necessary; simply packaging existing materials in new ways could enhance their properties. Potentially, our platform could be an enabling technology ‘beyond 3-D printing manufacturing’ to control materials at much smaller scales and with greater material variety and designed compositions. Using the same approach to form 3-D lattices from desired nano-objects of different material classes, integrating those that would otherwise be considered incompatible, could revolutionize nanomanufacturing.”
Cancer cell during cell division. Credit: National Institutes of Health
A new study at the University of Georgia has found a way to attack cancer cells that is potentially less harmful to the patient.
Sodium chloride nanoparticles—more commonly known as salt—are toxic to cancer cells and offer the potential for therapies that have fewer negative side effects than current treatments.
Led by Jin Xie, associate professor of chemistry, the study found that SCNPs can be used as a Trojan horse to deliver ions into cells and disrupt their internal environment, leading to cell death. SCNPs become salt when they degrade, so they’re not harmful to the body.
“This technology is well suited for localized destruction of cancer cells,” said Xie, a faculty member in the Franklin College of Arts and Sciences. “We expect it to find wide applications in treatment of bladder, prostate, liver, and head and neck cancer.”
Nanoparticles are the key to delivering SCNPs into cells, according to Xie and the team of researchers. Cell membranes maintain a gradient that keeps relatively low sodium concentrations inside cells and relatively high sodium concentrations outside cells.
The plasma membrane prevents sodium from entering a cell, but SCNPs are able to pass through because the cell doesn’t recognize them as sodium ions.
Once inside a cell, SCNPs dissolve into millions of sodium and chloride ions that are trapped inside by the gradient and overwhelm protective mechanisms, inducing rupture of the plasma membrane and cell death. When the plasma membrane ruptures, the molecules that leak out signal the immune system that there’s tissue damage, inducing an inflammatory response that helps the body fight pathogens.
“This mechanism is actually more toxic to cancer cells than normal cells, because cancer cells have relatively high sodium concentrations to start with,” Xie said.
Using a mouse model, Xie and the team tested SCNPs as a potential cancer therapeutic, injecting SCNPs into tumors. They found that SCNP treatment suppressed tumor growth by 66 percent compared to the control group, with no drop in body weight and no sign of toxicity to major organs.
They also performed a vaccination study, inoculating mice with cancer cells that had been killed via SCNPs or freeze thaw. These mice showed much greater resistance to a subsequent live cancer cell challenge, with all animals remaining tumor free for more than two weeks.
The researchers also explored anti-cancer immunity in a tumor model. After injecting primary tumors with SCNPs and leaving secondary tumors untreated, they found that the secondary tumors grew at a much lower speed than the control, showing a tumor inhibition rate of 53 percent.
Collectively, the results suggest that SCNPs killed cancer cells and converted the dying cancer cells to an in situ vaccine.
SCNPs are unique in the world of inorganic particles because they are made of a benign material, and their toxicity is based on the nanoparticle form, according to Xie.
“With a relatively short half-life in aqueous solutions, SCNPs are best suited for localized rather than systemic therapy. The treatment will cause immediate and immunogenic cancer cell death,” he said. “After the treatment, the nanoparticles are reduced to salts, which are merged with the body’s fluid system and cause no systematic or accumulative toxicity. No sign of systematic toxicity was observed with SCNPs injected at high doses.”
The study was published in Advanced Materials.
Researchers at Columbia University and University of California, San Diego, have introduced a novel “multi-messenger” approach to quantum physics that signifies a technological leap in how scientists can explore quantum materials.
The findings appear in a recent article published in Nature Materials, led by A. S. McLeod, postdoctoral researcher, Columbia Nano Initiative, with co-authors Dmitri Basov and A. J. Millis at Columbia and R.A. Averitt at UC San Diego.
“We have brought a technique from the inter-galactic scale down to the realm of the ultra-small,” said Basov, Higgins Professor of Physics and Director of the Energy Frontier Research Center at Columbia. Equipped with multi-modal nanoscience tools we can now routinely go places no one thought would be possible as recently as five years ago.”
The work was inspired by “multi-messenger” astrophysics, which emerged during the last decade as a revolutionary technique for the study of distant phenomena like black hole mergers. Simultaneous measurements from instruments, including infrared, optical, X-ray and gravitational-wave telescopes can, taken together, deliver a physical picture greater than the sum of their individual parts.
The search is on for new materials that can supplement the current reliance on electronic semiconductors. Control over material properties using light can offer improved functionality, speed, flexibility and energy efficiency for next-generation computing platforms.
Experimental papers on quantum materials have typically reported results obtained by using only one type of spectroscopy. The researchers have shown the power of using a combination of measurement techniques to simultaneously examine electrical and optical properties.
The researchers performed their experiment by focusing laser light onto the sharp tip of a needle probe coated with magnetic material. When thin films of metal oxide are subject to a unique strain, ultra-fast light pulses can trigger the material to switch into an unexplored phase of nanometer-scale domains, and the change is reversible.
By scanning the probe over the surface of their thin film sample, the researchers were able to trigger the change locally and simultaneously manipulate and record the electrical, magnetic and optical properties of these light-triggered domains with nanometer-scale precision.
The study reveals how unanticipated properties can emerge in long-studied quantum materials at ultra-small scales when scientists tune them by strain.
“It is relatively common to study these nano-phase materials with scanning probes. But this is the first time an optical nano-probe has been combined with simultaneous magnetic nano-imaging, and all at the very low temperatures where quantum materials show their merits,” McLeod said. “Now, investigation of quantum materials by multi-modal nanoscience offers a means to close the loop on programs to engineer them.”
The study, “Multi-messenger nanoprobes of hidden magnetism in a strained manganite,” was developed with support from Programmable Quantum Materials, an Energy Frontier Research Center funded by the United States Department of Energy (DOE), Office of Science and Basic Energy Sciences.
Nanomedicine researchers have successfully programmed nanorobots to find tumors and cut off their blood supply while leaving healthy tissue unharmed.
While we are living in an unprecedented level of digital disruption, we still face significant threats and challenges to our health and livelihoods. Everything from intensifying hurricanes due to climate change and increasing levels of income inequality will likely be issues that we confront in the decades to come. However, nanobots are perhaps not the most known digital innovations of this era, but they will become more and more visible now, especially considering cancer treatment!
Another key challenge that we face today is finding cures to devastating diseases—specifically cancer. The statistics are grim and researchers all around the world are working hard to find a way to develop a cure for cancer. While we aren’t quite there yet, one promising technology that may be able to help cure cancer are nanobots.
Nanobots are extremely exciting pieces of technology that are already being used for cancer treatment. Yes, the jury is still out on whether nanorobotics will become a cheap, yet extremely effective way to treat grave illnesses. Nevertheless, this is a technology that is certainly worth monitoring in the years to come and cancer will have a new enemy which is called nanobots.
NANOBOTS: A BRIEF DESCRIPTION
As a basic starting point, nanobots are tiny devices (ranging in size from 0.1 to 10 micrometers) that are constructed out of nanoscale or molecular components. For the sake of comparison, a red blood cell is approximately 0.1 to 10 micrometers. The essential idea of nanorobotics (nanobots) is that these tiny devices carry out certain procedures and instructions to solve a certain problem—all at an extremely small scale. To put it another way, nanobots are machines that can build and manipulate things with an extremely high degree of precision at an atomic level.
Some of the potential applications of nanobots include medical imaging, information storage devices, smart windows and walls, and even connecting our brains to the Internet. Already, researchers have already made several significant advancements in the technical aspects of nanorobotics. For example, several different groups of researchers have developed a “high-speed, remote-controlled nanoscale version of a rocket by combining nanoparticles with biological molecules.” Physicists from the University of Mainz have developed the so-called “smallest engine ever created” from a solitary atom. For more details on these (and other) advancements, click here.
TAKING THE FIGHT TO CANCER
We are still in the early days of nanorobotics, yet we have already seen the promise of nanobots being used to treat cancer. One of the most exciting studies came from researchers from Arizona State University and the National Center for Nanoscience and Technology of the Chinese Academy of Sciences. These researchers injected nanobots into the bloodstream of mice, and these nanobots targeted blood vessels around cancerous tumors. The nanobots, by using their embedded blood clotting drugs to cut off these blood vessels’ blood supply, were able to shrink the tumors and inhibit their spread. They were able to precisely target cancerous tumors and do it much more effectively than a surgeon with a scalpel ever could.
Another study from earlier this year used a DNA nanorobot that successfully sought out breast cancer cells in mice and targeted a specific protein. The researchers used nanobots to lower levels of a protein called human epidermal growth factor receptor 2 (HER2), which helps cancer cells proliferate uncontrollably. While the nanobot would need significantly more improvement before widespread use, it is yet another promising illustration of nanobots being used to treat cancer.
WHAT LIES AHEAD
Nanorobotics is tremendously exciting. That said, whether they are being used to treat cancer or create smart windows and walls, researchers need to overcome some significant challenges. For instance, researchers are still trying to determine an effective way to get these minuscule robots to travel to (and stay) at certain points in the body. Nanobots also need to avoid being expelled from the body by things like toxic or foreign bodies.
Once again, we are still in early innings. Researchers are going to need to invest a large amount of time, energy, and money into overcoming these challenges. There is no guarantee that the potential applications of nanorobotics will be available in our day-to-day lives.
But that said, the potential is there. Researchers have already made some significant progress, and it is likely that more is on the way. Whether you work in an industry that may be disrupted by nanorobotics or are simply interested in the technology, the next few years will certainly be fascinating.
A multidisciplinary group of engineers and scientists has discovered a new method for water filtration that could have implications for a variety of technologies, such as desalination plants, breathable and protective fabrics, and carbon capture in gas separations. The research team, led by Manish Kumar in the Cockrell School of Engineering at The University of Texas at Austin, published their findings in the latest issue of Nature Nanotechnology.
The study, which brought together researchers from UT Austin, Penn State University, the University of Tennessee, Fudan University and the University of Illinois at Urbana-Champaign, was initially inspired by the way our cells transport water throughout the body and began as an attempt to develop artificial channels for transporting water across membranes. The aim was to mimic aquaporins, essential membrane proteins that serve as water channels and are found in certain cells. Aquaporins are fast and efficient water filtration systems. They form pores in the membranes of cells in various parts of the body—eyes, kidneys and lungs—where water is in greatest demand.
Kumar and the team didn’t manage to mirror the aquaporin system exactly as planned. Instead, they discovered an even more effective water filtration process. Unlike the body’s individual aquaporin cells, which function effectively independent of one another, the membranes developed by Kumar’s research group didn’t work well alone.
But, when he combined several of them to create networks of “water wires,” they were highly effective at water transport and filtration. Water wires are densely connected chains of water molecules that move exceptionally fast, like a train and its individual cars.
“We were trying to copy the already complicated water transport process used by aquaporins and stumbled upon an entirely new, and even better, method,” said Kumar, an associate professor in the Cockrell School’s Department of Civil, Architectural and Environmental Engineering. “It was completely serendipitous. We had no idea it would happen.”
These networks of artificial membranes could prove useful for separating salt from water, a filtration process that is currently inefficient and costly. The new membrane has shown impressive desalination properties, exhibiting far more selective salt and presumably other contaminant removal when compared with existing processes.
“Our method is a thousand times more efficient than current desalination processes in terms of its selectivity and permeability,” Kumar said. “For every 10,000 saltwater molecules that pass through current desalination systems, one salt molecule might not be filtered out. With our new membrane technology, one salt molecule for every 10 million water molecules would not be filtered out, while maintaining a water transport rate comparable to or better than current membranes.”
For his entire career, Kumar has focused on developing materials and processes that take the functionality of biological molecular models and apply them into engineering scales.
“It is difficult to even effectively mimic the complexities of how the human body works, especially at the molecular level,” he said. “This time, however, nature was the starting point for an even greater discovery than we could have ever hoped for.”
More information: Woochul Song et al, Artificial water channels enable fast and selective water permeation through water-wire networks, Nature Nanotechnology (2019). DOI: 10.1038/s41565-019-0586-8