Lună: august 2016

Wi-fi de la lasere pe bază de nanocristal(Wi-fi from nanocrystal-based lasers)

Un material nanocristalin care face rapid lumina alba din lumina albastra a fost dezvoltat de cercetatorii KAUST pentru iluminarea combinată și comunicarea de date.

Posted: Aug 15, 2016

Wi-fi from nanocrystal-based lasers

(Nanowerk News) A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers (ACS Photonics, „Perovskite Nanocrystals as a Color Converter for Visible Light Communication”).
Light Data Transfer
A nanocrystal-based material converts blue laser emission to white light for combined illumination and data communication. (Image: KAUST)
While Wi-Fi and Bluetooth are now well established technologies, there are several advantages gained by shortening the wavelength of the electromagnetic waves used for transmitting information.
So-called visible-light communication (VLC) makes use of parts of the electromagnetic spectrum that are unregulated and is potentially more energy-efficient. VCL also offers a way to combine information transmission with illumination and display technologies–for example, using ceiling lights to provide internet connections to laptops.
Many such VLC applications require light-emitting diodes (LEDs) that produce white light. These are usually fabricated by combining a diode that emits blue light with phosphorous that turns some of this radiation into red and green light. However, this conversion process is not fast enough to match the speed at which the LED can be switched on and off.
„VLC using white light generated in this way is limited to about one hundred million bits per second,” said KAUST Professor of Electrical Engineering Boon Ooi.
Instead, Ooi, , Associate Professor Osman Bakr and their colleagues use a nanocrystal-based converter that enables much higher data rates.
The team created nanocrystals of cesium lead bromide that were roughly eight nanometers in size using a simple and cost-effective solution-based method that incorporated a conventional nitride phosphor. When illuminated by a blue laser light, the nanocrystals emitted green light while the nitride emitted red light. Together, these combined to create a warm white light.
The researchers characterized the optical properties of their material using a technique known as femtosecond transient spectroscopy. They were able to show that the optical processes in cesium lead bromide nanocrystals occur on a time-scale of roughly seven nanoseconds. This meant they could modulate the optical emission at a frequency of 491 Megahertz, 40 times faster than is possible using phosphorus, and transmit data at a rate of two billion bits per second.
„The rapid response is partly due to the size of the crystals,” said Bakr. „Spatial confinement makes it more likely that the electron will recombine with a hole and emit a photon.”
Importantly, the white light generated using their perovskite nanostructures was of a quality comparable to present LED technology.
„We believe that white light generated using semiconductor lasers will one day replace the LED white-light bulbs for energy-efficient lighting,” said Ooi.
Source: King Abdullah University of Science & Technology

Noua descoperire de materiale permite studiul fermionului Weyl evaziv(New material discovery allows study of elusive Weyl fermion)

au descoperit un nou tip de semimetal Weyl, un material care deschide calea pentru studiul în continuare a fermiunilor Weyl, un tip de particule elementare fără masa, ipotezat de teoria particulelor de energie înaltă și potențial util pentru crearea de circuite electronice de mare viteză și computere cuantice.Cercetătorii au creat un cristal de molibden și telur, unul dintre puținele compuși care se presupune că găzduiesc un tip nou de Weyl, postulat, în care benzile electronice și electronice se separă în mod normal printr-o atingere indirectă la câteva puncte Weyl. Aceste puncte sunt echivalente cu monopolurile magnetice din spațiul de impuls și sunt conectate prin arce Fermi.

Posted: Aug 15, 2016

New material discovery allows study of elusive Weyl fermion

(Nanowerk News) Researchers at the U.S. Department of Energy’s Ames Laboratory have discovered a new type of Weyl semimetal, a material that opens the way for further study of Weyl fermions, a type of massless elementary particle hypothesized by high-energy particle theory and potentially useful for creating high-speed electronic circuits and quantum computers (Nature Materials, „Spectroscopic evidence for a type II Weyl semimetallic state in MoTe2„).
Spectroscopic evidence for a type II Weyl semimetallic state in MoTe
Researchers created a crystal of molybdenum and tellurium, one of only a few compounds that had been predicted to host a new and recently postulated type of Weyl state, where the hole and electron bands normally separated by an indirect gap touch at a few Weyl points. Those points are equivalent to magnetic monopoles in the momentum space and are connected by Fermi arcs.
A combination of angle resolved photoemission spectroscopy (ARPES), modelling, density functional theory and careful calculations were used to confirm the existence of this new type of Weyl semimetal.
This material provides an exciting new platform to study the properties of Weyl fermions, and may lead the way to more new materials with unusual transport properties.
„This an important, interdisciplinary discovery because it allows us to study many aspects of these exotic particles predicted by high energy physics theory in solid state, without need for extremely expensive particle accelerators,” said Adam Kaminsky, Ames Laboratory scientist and professor in the Department of Physics and Astronomy at Iowa State University. „From my perspective as solid state physicist it is absolutely extraordinary to observe two bands touching each other at certain points and being connected by Fermi arcs – objects that are prohibited to exist in „ordinary” materials.”
Source: Ames Laboratory

„Plasmonele de sniffer” ar putea detecta o singură moleculă de explozivi(‘Sniffer plasmons’ could detect a single molecule of explosives)

au descoperit că forma bi-dimensională a carbonului, cunoscută sub numele de grafen, ar putea fi materialul ideal pentru fabricarea dispozitivelor plasmonice capabile să detecteze materiale explozive, substanțe chimice toxice alți compuși organici bazați pe o singură moleculă, afirmă un articol publicat în Physical Review B ( „Descrierea de sine strictă a amplificatorului cuantic al grafeinei” ).Dispozitivul de spargere de grafen poate fi utilizat pentru a proiecta dispozitive compacte de măsurare spectrală capabile să detecteze chiar și o singură moleculă dintr-o substanță, care este esențială pentru multe aplicații potențiale. Astfel de senzori ar putea detecta moleculele organice pe baza tranzițiilor lor vibraționale caracteristice („amprentele digitale”), deoarece lumina emisă / absorbită cade în regiunea infraroșie medie, care este exact în cazul în care funcționează spaserul bazat pe grafeni

Posted: Aug 15, 2016

‘Sniffer plasmons’ could detect a single molecule of explosives

(Nanowerk News) Physicists from the Moscow Institute of Physics and Technology (MIPT) have found that the two-dimensional form of carbon, known as graphene, might be the ideal material for manufacturing plasmonic devices capable of detecting explosive materials, toxic chemicals, and other organic compounds based on a single molecule, says an article published in Physical Review B („Self-consistent description of graphene quantum amplifier”).
Design of a spaser with the graphene layer shown as a honeycomb lattice above the dielectric layer
Design of the spaser with the graphene layer shown as a honeycomb lattice above the dielectric layer (blue). The spaser is optically pumped through the active (gain) medium shown in orange.
Plasmons in constructing high-accuracy electronics and optics
Scientists have long been fascinated by the potential applications of a quasiparticle called the plasmon, a quantum of plasma oscillations. In the case of a solid body, plasmons are the oscillations of free electrons. Of special interest are the effects arising from the surface interactions of electromagnetic waves with plasmons—usually in the context of metals or semimetals, as they have a higher free electron density. Harnessing these effects could bring about a breakthrough in high-accuracy electronics and optics. One possibility opened up by plasmonic effects is the subwavelength light focusing, which increases the sensitivity of plasmonic devices to a point where they can distinguish a single molecule. Such measurements are beyond what any conventional (classical) optical devices can achieve. Unfortunately, plasmons in metals tend to lose energy quickly due to resistance, and for this reason they are not self-sustained, i.e. they need continuous excitation. Scientists are trying to tackle this issue by using composite materials with predefined microstructure, including graphene.
Graphene is an allotrope of carbon in the form of a two-dimensional crystal. It can be visualised as a one-atom-thick honeycomb lattice made of carbon atoms. Two MIPT graduates, Andre Geim and Konstantin Novoselov, were the first to isolate graphene, which won them a Nobel Prize in Physics. Graphene is a semiconductor with extremely high charge carrier mobility. Its electrical conductivity is also exceptionally high, which makes graphene-based transistors possible.
Theoretical physicists give the okay
Although, plasmonic devices have seemed an exciting prospect to pursue from the start, to take advantage of them, it was first necessary to find out whether the technology behind them was feasible. To do this, scientists had to find a numerical solution to the relevant quantum-mechanical equations. This was accomplished by a team of researchers at the Laboratory of Nanostructure Spectroscopy headed by Prof. Yurii Lozovik: they formulated and solved the necessary equation. Their research has led them to develop a quantum model that predicts plasmonic behaviour in graphene. As a result, the scientists described the operation of a surface-plasmon-emitting diode (SPED) and the nanoplasmonic counterpart of the laser—known as the spaser—whose construction involves a graphene layer.
A spaser could be described as a device similar to a laser and operating on the same basic principle. However, to produce radiation, it relies on optical transitions in the gain medium, and the particles emitted are surface plasmons, as opposed to photons produced by a laser. An SPED is different from a spaser in that it is an incoherent source of surface plasmons. It also requires considerably lower pump power. Both devices would operate within the infrared region of the spectrum, which is useful for studying biological molecules.
‘The graphene spaser could be used to design compact spectral measurement devices capable of detecting even a single molecule of a substance, which is essential for many potential applications. Such sensors could detect organic molecules based on their characteristic vibrational transitions (‘fingerprints’), as the light emitted/absorbed falls into the medium infrared region, which is exactly where the graphene-based spaser operates,’ says Alexander Dorofeenko, one of the authors of the study.
Source: Moscow Institute of Physics and Technology

Aparatul nanostructurat captează mai multă energie solară pentru a dezinfecta mai repede apa(Nanostructured device grabs more solar energy to disinfect water faster)

au creat un dispozitiv nanostructurat, aproximativ jumătate din dimensiunea unei ștampile poștale, care dezinfecteaza apa cu mult mai rapid decât metoda UV, folosind de asemenea partea vizibilă a spectrului solar , care conține 50% din energia soarelui

Posted: Aug 15, 2016

Nanostructured device grabs more solar energy to disinfect water faster

(Nanowerk News) In many parts of the world, the only way to make germy water safe is by boiling, which consumes precious fuel, or by putting it out in the sun in a plastic bottle so ultraviolet rays will kill the microbes. But because UV rays carry only 4 percent of the sun’s total energy, the UV method takes six to 48 hours, limiting the amount of water people can disinfect this way.
Now researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University have created a nanostructured device, about half the size of a postage stamp, that disinfects water much faster than the UV method by also making use of the visible part of the solar spectrum, which contains 50 percent of the sun’s energy.
This nanostructured device uses sunlight to quickly disinfect water
This nanostructured device, about half the size of a postage stamp, uses sunlight to quickly disinfect water. It consists of thin flakes of molybdenum disulfide arranged like walls on a glass surface and topped with a thin layer of copper. Light falling on the walls triggers formation of hydrogen peroxide (H2O2) and other “reactive oxygen species” that kill bacteria. (Image: C. Liu et al., Nature Nanotechnology)
In experiments reported today in Nature Nanotechnology („Rapid water disinfection using vertically aligned MoS2 nanofilms and visible light”), sunlight falling on the little device triggered the formation of hydrogen peroxide and other disinfecting chemicals that killed more than 99.999 percent of bacteria in just 20 minutes. When their work was done the killer chemicals quickly dissipated, leaving pure water behind.
“Our device looks like a little rectangle of black glass. We just dropped it into the water and put everything under the sun, and the sun did all the work,” said Chong Liu, lead author of the report. She is a postdoctoral researcher in the laboratory of Yi Cui, a SLAC/Stanford associate professor and investigator with SIMES, the Stanford Institute for Materials and Energy Sciences at SLAC.
Nanoflake Walls and Eager Electrons
Under an electron microscope the surface of the device looks like a fingerprint, with many closely spaced lines. Those lines are very thin films – the researchers call them “nanoflakes” – of molybdenum disulfide that are stacked on edge, like the walls of a labyrinth, atop a rectangle of glass.
In ordinary life, molybdenum disulfide is an industrial lubricant. But like many materials, it takes on entirely different properties when made in layers just a few atoms thick. In this case it becomes a photocatalyst: When hit by incoming light, many of its electrons leave their usual places, and both the electrons and the “holes” they leave behind are eager to take part in chemical reactions.
By making their molybdenum disulfide walls in just the right thickness, the scientists got them to absorb the full range of visible sunlight. And by topping each tiny wall with a thin layer of copper, which also acts as a catalyst, they were able to use that sunlight to trigger exactly the reactions they wanted – reactions that produce “reactive oxygen species” like hydrogen peroxide, a commonly used disinfectant, which kill bacteria in the surrounding water.
Molybdenum disulfide is cheap and easy to make – an important consideration when making devices for widespread use in developing countries, Cui said. It also absorbs a much broader range of solar wavelengths than traditional photocatalysts.
Solving Pollution Problems
The method is not a cure-all; for instance, it doesn’t remove chemical pollutants from water. So far it’s been tested on only three strains of bacteria, although there’s no reason to think it would not kill other bacterial strains and other types of microbes, such as viruses. And it’s only been tested on specific concentrations of bacteria mixed with less than an ounce of water in the lab, not on the complex stews of contaminants found in the real world.
Still, “It’s very exciting to see that by just designing a material you can achieve a good performance. It really works,” said Liu, who has gone on to work on a project in Cui’s lab that is developing air filters for combating smog. “Our intention is to solve environmental pollution problems so people can live better.”
Source: SLAC National Accelerator Laboratory

Metamaterial care schimba forma, dezvoltat folosind tehnica Kirigami ( Shape-changing metamaterial developed using Kirigami technique)

au dezvoltat un nou metamaterial care schimba forma folosind Kirigami, arta antica japoneza de taiere si pliere a hartiei pentru a obtine forme 3D.Metamaterialele sunt o clasă de materiale proiectate pentru a produce proprietăți care nu apar în mod natural. În prezent, metamaterialele sunt folosite pentru a face absorbanți artificiali și vibrații artificiali și senzori de înaltă performanță. Kirigami poate fi aplicat pentru a transforma materialele din tablă bidimensională în forme tridimensionale complexe cu o gamă mai largă de geometrii decât origami „clasice”.

Posted: Aug 05, 2016

Shape-changing metamaterial developed using Kirigami technique

(Nanowerk News) Engineers from the University of Bristol have developed a new shape-changing metamaterial using Kirigami, which is the ancient Japanese art of cutting and folding paper to obtain 3D shapes.
Open Honeycomb
This image shows an open honeycomb at each stage during the manufacturing process. (Image: University of Bristol)
Metamaterials are a class of material engineered to produce properties that don’t occur naturally. Currently metamaterials are used to make artificial electromagnetic and vibration absorbers and high-performance sensors. Kirigami can be applied to transform two-dimensional sheet materials into complex three-dimensional shapes with a broader choice of geometries than ‘classical’ origami.
The research, developed within a PhD programme run by the University’s EPSRC Centre for Doctoral Training in Advanced Composites for Innovation and Science (ACCIS CDT), is published in Scientific Reports („Shape morphing Kirigami mechanical metamaterials”).
The type of mechanical metamaterials using the Kirigami technique, developed by PhD student Robin Neville, changes shape seamlessly, exhibits large variations in mechanical performance with small geometry changes, and can be adapted to modify its configuration by using mainstream actuation mechanisms.
Bending Behavior
This image shows bending behavior. (a) Synclastic curvature in the closed configuation; (b) cylindrical curvature in the open rec configurations; (c) an open rec specimen folder double. (Image: University of Bristol) (click on image to enlarge)
The Kirigami metamaterial can also be produced using off-the-shelf thermoplastic or thermoset composite materials, and different sensing and electronics systems can be embedded to obtain a fully integrated smart shape-changing structure.
Fabrizio Scarpa, Professor of Smart Materials and Structures in the Department of Aerospace Engineering and ACCIS, said: „Mechanical metamaterials exhibit unusual properties through the shape and deformation of their engineered subunits. Our research presents a new investigation of the kinematics of a family of cellular metamaterials based on Kirigami design principles. This technique allows us to create cellular structures with engineered cuts and folds that produce large shape and volume changes, and with extremely directional, tuneable mechanical properties.”
Honeycomb Morphing
This is a demonstrator honeycomb changing shape in response to cable tension. The arrows indicate which cable is being pulled. (Image: University of Bristol)
Robin Neville, PhD student, added: „By combining analytical models and numerical simulations we have demonstrated how these Kirigami cellular metamaterials can change their deformation characteristics. We have also shown the potential of using these classes of mechanical metamaterials for shape change applications like morphing structures.”
In the future, this Kirigami metamaterial could be used in robotics, morphing structures for airframe and space applications, microwave and smart antennas.
Source: University of Bristol

Read more: Shape-changing metamaterial developed using Kirigami technique

Dezvoltarea unui nou „vas” de nanomateriale de carbon ( Development of a novel carbon nanomaterial ‘pot’

Din analiza detaliata a suprafetei, s-au gasit grupuri hidroxil hidrofile grupate de-a lungul suprafetei exterioare a corpului de nanopot de carbon”, a spus Associate Prof. Yokoi. „Grapena este de obicei hidrofobă, totuși, dacă grupările hidroxil sunt împachetate dens pe suprafața exterioară a corpului, zona respectivă va fi hidrofilă. Cu alte cuvinte, nanopotul de carbon ar putea fi un nanomaterial unic, cu caracteristici hidrofobe și hidrofile. Procesul de realizare a unei analize de suprafață mai sofisticate pentru a obține acea asigura

Posted: Aug 05, 2016

Development of a novel carbon nanomaterial ‘pot’

(Nanowerk News) A novel, pot-shaped, carbon nanomaterial developed by researchers from Kumamoto University, Japan is several times deeper than any hollow carbon nanostructure previously produced. This unique characteristic enables the material to gradually release substances contained within and is expected to be beneficial in applications such as drug delivery systems.
Transmission Electron Microscope Image of Carbon Nanopots
Carbon nanopots are made of several different laminated graphene layer structures as labeled by the yellow text. The magnified image (inset) reveals the area indicated by the dashed line in the main image. The numerical value in the inset is the average value of layer spacing, and the arrows indicate graphene edges exposed on the outer surface of the body. (© Materials Research Society, Dr. Eng. Hiroyuki Yokoi)
Carbon is an element that is light, abundant, has a strong binding force, and eco-friendly. The range of carbon-based materials is expected to become more widespread in the eco-friendly society of the future. Recently, nanosized (one-billionth of a meter) carbon materials have been developed with lengths, widths, or heights below 100 nm. These materials take extreme forms such as tiny grained substances, thin sheet-like substances, and slim fibrous substances. Example of these new materials are fullerenes, which are hollow cage-like carbon molecules; carbon nanotubes, cylindrical nanostructures of carbon molecules; and graphene, one-atom thick sheets of carbon molecules.
Why are these tiny substances needed? One reason is that reactions with other materials can be much larger if a substance has an increased surface area. When using nanomaterials in place of existing materials, it is possible to significantly change surface area without changing weight and volume, thereby improving both size and performance. The development of carbon nanomaterials has provided novel nanostructured materials with shapes and characteristics that surpass existing materials.
Now, research from the laboratory of Kumamoto University’s Associate Prof. Yokoi has resulted in the successful development of a container-type carbon nanomaterial with a much deeper orifice than that found in similar materials (Journal of Materials Research, „Novel pot-shaped carbon nanomaterial synthesized in a submarine-style substrate heating CVD method”).
Transmission Electron Microscope Image of Carbon Nanopot fiber
The black arrow indicates the end of the opening of carbon nanopot. A structural schematic of the carbon nanopot showing hydroxyl groups bonded to the edges of the graphene layers near the closed end of the nanopot is also indicated (not to scale). (© Materials Research Society)
To create the new material, researchers used their own, newly developed method of material synthesis. The container-shaped nanomaterial has a complex form consisting of varied layers of stacked graphene at the bottom, the body, and the neck areas of the container, and the graphene edges along the outer surface of the body were found to be very dense. Due to these innovate features, Associate Prof. Yokoi and colleagues named the material the „carbon nanopot.”
The carbon nanopot has an outer diameter of 20 ~ 40 nm, an inner diameter of 5 ~ 30 nm, and a length of 100 ~ 200 nm. During its creation, the carbon nanopot is linked to a carbon nanofiber with a length of 20 ~ 100 µm meaning that the carbon nanopot is also available as a carbon nanofiber. At the junction between nanopots, the bottom of one pot simply sits on the opening of the next without sharing a graphene sheet connection. Consequently, separating nanopots is very easy.
„From a detailed surface analysis, hydrophilic hydroxyl groups were found clustered along the outer surface of the carbon nanopot body,” said Associate Prof. Yokoi. „Graphene is usually hydrophobic however, if hydroxyl groups are densely packed on the outer surface of the body, that area will be hydrophilic. In other words, carbon nanopots could be a unique nanomaterial with both hydrophobic and hydrophilic characteristics. We are currently in the process of performing a more sophisticated surface analysis in order to get that assurance.”
Since this new carbon nanopot has a relatively deep orifice, one of its expected uses is to improve drug delivery systems by acting as a new foundation for medicine to be carried into and be absorbed by the body.
Source: Kumamoto University

Read more: Development of a novel carbon nanomaterial ‘pot’

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Primul lucru pe care îl observați despre Recon Trainer este cât de ușor și de perceptiv se simte când îl puneți

5 sept

Cadrele metalice și organice găsite în natură(Metal-organic frameworks found to exist in nature)

Unul dintre cele mai fierbinți materiale noi este o clasă de substanțe solide poroase, cunoscute sub numele de cadre metalice organice sau MOF. Aceste materiale artificiale au fost introduse în anii 1990, iar cercetătorii din întreaga lume lucrează la modalități de utilizare a acestora ca bureți moleculari pentru aplicații cum ar fi stocarea hidrogenului, sechestrarea carbonului sau fotovoltaica. Acum, o descoperire surprinzătoare a oamenilor de știință din Canada și Rusia relevă faptul că MF există, de asemenea, în natură – deși sub formă de minerale rare găsite până acum numai în minele de cărbune din Siberia.

Posted: Aug 05, 2016

Metal-organic frameworks found to exist in nature

(Nanowerk News) One of the hottest new materials is a class of porous solids known as metal-organic frameworks, or MOFs. These man-made materials were introduced in the 1990s, and researchers around the world are working on ways to use them as molecular sponges for applications such as hydrogen storage, carbon sequestration, or photovoltaics. Now, a surprising discovery by scientists in Canada and Russia reveals that MOFs also exist in nature – albeit in the form of rare minerals found so far only in Siberian coal mines.
The finding, published in the journal Science Advances („Minerals with metal-organic framework structures”), „completely changes the normal view of these highly popular materials as solely artificial, ‘designer’ solids,” says senior author Tomislav Friscic, an associate professor of chemistry at McGill University in Montreal. „This raises the possibility that there might be other, more abundant, MOF minerals out there.”
synthetic zhemchuzhnikovite
An aggregate of synthetic zhemchuzhnikovite, prepared by Igor Huskić, McGill University)
The twisting path to the discovery began six years ago, when Friscic came across a mention of the minerals stepanovite and zhemchuzhnikovite in a Canadian mineralogy journal. The crystal structure of the minerals, found in Russia between the 1940s and 1960s, hadn’t been fully determined. But the Russian mineralogists who discovered them had analyzed their chemical composition and the basic parameters of their structures, using a technique known as X-ray powder diffraction. To Friscic, those parameters hinted that the minerals could be structurally similar to a type of man-made MOF.
His curiosity piqued, Friscic began looking for samples of the rare minerals, reaching out to experts, museums and vendors in Russia and elsewhere. After a promising lead with a mining museum in Saint Petersburg failed to pan out, Igor Huskic, a graduate student in the Friscic research group at McGill turned his attention to synthesizing analogues of the minerals in the lab – and succeeded. But a major journal last year declined to publish the team’s work, in part because the original description of the minerals had been reported in a somewhat obscure Russian mineralogical journal.
Then, the McGill chemists caught a break: with the help of a crystallographer colleague in Venezuela, they connected with two prominent Russian mineralogists: Sergey Krivovichev, a professor at Saint Petersburg State University, and Prof. Igor Pekov of Lomonosov Moscow State University.
Krivovichev and Pekov were able to obtain the original samples of the two rare minerals, which had been found decades earlier in a coal mine deep beneath the Siberian permafrost. The Russian experts were also able to determine the crystal structures of the minerals. These findings confirmed the McGill researchers’ initial results from their lab synthesis.
zhemchuzhnikovite mineral
Fragment of the crystal structure of the natural zhemchuzhnikovite mineral.
Stepanovite and zhemchuzhnikovite have the elaborate, honeycomb-like structure of MOFs, characterized at the molecular level by large voids. The two minerals aren’t, however, representative of the hottest varieties of MOFs – those that are being developed for use in hydrogen-fueled cars or to capture waste carbon dioxide.
As a result, Friscic and his collaborators are now broadening their research to determine if other, more abundant minerals have porous structures that could make them suitable for uses such as hydrogen storage or even drug delivery.
In any event, the discovery of MOF structures in the two rare minerals already is „paradigm-changing” Friscic says. If scientists had been able to determine those structures in the 1960s, he notes, the development of MOF materials „might have been accelerated by 30 years.”
Source: McGill University

Read more: Metal-organic frameworks found to exist in nature