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Chemistry and Nanotechnology

Category
Technology Name
Briefcase
Scientist
1783
Aluminum and magnesium alloys are gaining more recognition for light-weight materials applications. In spite of this, such alloys have not been used for critical mechanical applications mainly due to their inferior mechanical properties compared to other engineering materials such as steel. Hence, many...

Aluminum and magnesium alloys are gaining more recognition for light-weight materials applications. In spite of this, such alloys have not been used for critical mechanical applications mainly due to their inferior mechanical properties compared to other engineering materials such as steel. Hence, many researchers have attempted to reinforce these alloys and obtain light-weight materials with excellent mechanical properties. The reinforcement process of the alloy can be achieved by introducing another material to form metal matrix composites. Different studies show that such composites exhibit improved properties, such as increased yield strength and tensile strength, enhanced stiffness, improved thermochemical properties, etc. However, the introduction of nanomaterials into the metal matrix is rather difficult due to the harsh manufacturing conditions employed for processing the metal composites.

The group of Prof. Reshef Tenne has developed state-of-the-art aluminum- and magnesium-based metal matrix composites, comprising small amounts of inorganic nanomaterials, such as nanotubes and spherical nanoparticles. The new nanocomposites exhibit much superior mechanical properties compared to the pristine alloy.

Applications


·         Automotive, transportation, and aerospace industries

·         Jet engine technologies

·         Electronics

·         Medical technologies


Advantages


·         Light-weight metal alloys

·         Excellent mechanical properties

·         Straight-forward fabrication technique


Technology's Essence


Aluminum (AA6061) and magnesium (AZ31) alloys were combined with small amounts (up to 1 wt.%) of either tungsten disulfide nanotubes or inorganic fullerene-like tungsten disulfide nanoparticles to form metal matrix composites using a melt-stirring reactor operated at high temperatures (up to 750oC). These nano-structures exhibit unique mechanical properties, which make their usage as composite fillers very promising, and a remarkable stability at elevated processing temperatures. Despite the small amounts of added nanostructures, their addition led to notable improvements in the mechanical properties of the alloys. Surprisingly, both the tensile strength of the alloys and their elongation (and consequently the fracture toughness) were improved by 10-20%. Depending on the nano-structure type and concentration, the hardness, yielding strength, ultimate tensile strength, and ductility were improved by up to ~70%. Physical considerations suggest that the main mechanism responsible for the reinforcement effect lies in the mismatch between the thermal expansion coefficients of the metal and the nano-structures.

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  • Prof. Reshef Tenne
1786
Perovskites are a class of crystalline materials with a common complex chemical structure. Lead-halide hybrid organic-inorganic perovskites have recently emerged as highly efficient optoelectronic materials. Such materials are being intensively investigated and developed for photovoltaics,...

Perovskites are a class of crystalline materials with a common complex chemical structure. Lead-halide hybrid organic-inorganic perovskites have recently emerged as highly efficient optoelectronic materials. Such materials are being intensively investigated and developed for photovoltaics, photodetection, light-emitting diodes, and laser devices. Solar cells containing hybrid organic-inorganic perovskites have achieved over 20% certified efficiency.

Perovskites are most commonly synthesized by combining a metal salt (for example, a lead-based salt such as lead iodide) with an organic halide salt in a single step, by spin-coating from a solution of both salts, by co-evaporation, or by a two-step method of forming the metal salt film and subsequently exposing it to the organic halide. The existing fabrication methods suffer from high toxicity, complexity and high energy input.

We present a new method for the preparation of halide perovskites on a substrate for optoelectronic devices and solar cells, including tandem cells that produce higher voltages.

Applications


·      Solar cells

·      Other optoelectronic devices (e.g., photodetectors, light-emitting diodes, lasers)


Advantages


·      Reduced toxicity

·      Simple and straight-forward fabrication method

·      Excellent morphology control of the perovskites


Technology's Essence


Perovskites are crystalline materials with the formula ABX3, in which A and B are cations and X represents an anion. In hybrid organic–inorganic perovskites (HOIPs), A is an organic cation, B is a metal cation, and X is a halide anion.

The synthesis of HOIPs usually involves the use of toxic metal salts (for example, lead iodide or lead acetate) and organic solvents (such as dimethylformamide). Additionally, the combination of a metal salt with several organic solvents, such as dimethylsulfoxide, increases the toxicity of the solution in use.

The new fabrication method utilizes a metal or a metal alloy and an organic halide salt. In the first step, a layer comprising one of the components is deposited on a substrate. Then, the deposited layer is treated with a solution or a vapor of the second component to form a halide HOIP on a solid surface. This method provides a direct conversion of an elemental metal or a metal alloy to a halide perovskite or a perovskite related material. The main advantage of the presented method is the reduced toxicity of the solution used in the process. Additionally, the metals (mainly lead) are much less toxic in terms of manufacturing than the salts of the same metals.

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  • Prof. David Cahen
1798
The rising demand for exclusive visual impact in many applications, along with escalating regulatory requirements drive the development of new, environmentally benign, pearlescent materials. Guanine, a common naturally mineralized material, is being used in a variety of products in industries, such as...

The rising demand for exclusive visual impact in many applications, along with escalating regulatory requirements drive the development of new, environmentally benign, pearlescent materials. Guanine, a common naturally mineralized material, is being used in a variety of products in industries, such as cosmetics, paints and jewelry due to its pearlescence effect. However, the industrial application of guanine crystals is limited since they are extracted from biological sources (mostly fish scales) with limited control over crystals dimensions, morphology and quantity for industrial applications. The main reasons impeding the use of synthetic guanine crystals are guanine insolubility in most solvents and the difficulty of obtaining crystals in the desired morphology. For these reasons, there is a thriving need for the development of a synthetic approach for the formation of well-defined anhydrous guanine crystals with tailor-made properties.

The new technology provides a novel synthetic method for the preparation of highly versatile pearlescent materials, based on guanine crystals, from aqueous solutions. The controllable size and shape of the resulting materials and the sustainability of the method make them suitable alternatives for the existing naturally occurring pearlescent pigments.

Applications


·      Cost-effective and environmentally-friendly approach

·      Control over crystals properties, including size and phase (anhydrous guanine and guanine monohydrate)

·      The same technology can be applied for the crystallization of other materials (purines and pteridines)


Advantages


·      Cosmetics and personal care products

·      Printing inks and decorative paints

·      Automotive paints.


Technology's Essence


Guanine is practically insoluble in neutral aqueous solutions. However, in aqueous acidic or basic solutions, where the molecules are ionized, guanine is much more soluble. The process involves dissolving guanine powder in either acidic or basic solutions, using HCl or NaOH, respectively, and then inducing crystallization by adjusting the pH of the solution. The crystal morphologies differ significantly when carrying out the crystallization in solutions adjusted to different pH regimes. Using pH induced crystallization, the interplay between the initial guanine concentration and the rate of pH change allow substantial control over the crystallization process and ultimately over the crystal size.

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  • Prof. Lia Addadi
1716
An efficient and selective decomposition of plant biomass carbohydrates to their basic components, carbon monoxide and hydrogen, for use as syngas.Terrestrial plants contain about 70% hemicellulose and cellulose, which constitute a significant renewable bio-resource with potential as an alternative to...

An efficient and selective decomposition of plant biomass carbohydrates to their basic components, carbon monoxide and hydrogen, for use as syngas.
Terrestrial plants contain about 70% hemicellulose and cellulose, which constitute a significant renewable bio-resource with potential as an alternative to petroleum feedstock for carbon-based fuels. Traditional conversion of biomass to liquid fuels has been in the form of ethanol and bio-diesel, but this process is inefficient and much of the starting material is unusable and ultimately becomes waste.[1] Additionally, use of ethanol or bio-diesel is not universal to all engines as vehicles require specialized components to run on these fuels.
The presented technology allows for significantly greater efficiency in use of starting material, and the versatile final product of syngas, which can be a fuel itself or used as a fuel precursor in the well-known Fischer-Tropsch process to create hydrocarbons.[2] Alternatively, in a hydrogen economy scenario, this method can also be used to convert carbon monoxide to hydrogen via the water-gas shift reaction. Advantageously, both processes allow for the polyoxometalate (POM) catalyst to be reused without the need for recovery, which enables continuous use in a refinery setting.

Applications


  • Liquid hydrocarbon fuel synthesis from syngas
  • Entry into a new market – hydrogen production from biomass

Advantages


  • Efficient and complete breakdown of starting biomass material
  • Possible to produce hydrogen or syngas as product

Technology's Essence


The technology allows for preparation of syngas by reaction of a carbohydrate with a POM catalyst in the presence of a concentrated acid under anaerobic conditions, to yield carbon monoxide, followed by electrochemical release of hydrogen. This two-step process allows for easy separation and storage of the desired products. An alternative application of the same POM catalyst relates to a method for preparing formic acid in a similar method, but in a solvent consisting of a mixture of alcohol and water.
This reaction is based on the unexpected finding that POM catalysts, such as H5PV2Mo10O40, catalyze plant biomass derived polysaccharides of general form (CnH2nOn)m, with high selectivity and efficiency under mild conditions. Formation of CO occurs through an intermediate formation of formic acid and formaldehyde, and transformation of these transition compounds in concentrated acid results in the desired CO product. During this process, hydrogen atoms are stored on the POM catalysts as protons and electrons. Hydrogen gas is subsequently electrochemically released from the POM catalyst, which returns the catalyst to its original oxidized state and allows for continued reuse.

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  • Prof. Ronny Neumann
1730
Production of carbon nanotube based transistors through a process comprised of identification, selection, and placement of pristine carbon nanotubes in conjunction with standard electrical circuitry.Semiconductor devices are vital to everyday life, however conventional semiconducting materials are...

Production of carbon nanotube based transistors through a process comprised of identification, selection, and placement of pristine carbon nanotubes in conjunction with standard electrical circuitry.
Semiconductor devices are vital to everyday life, however conventional semiconducting materials are quickly approaching their limitations. As devices transition from the microscale to the nanoscale, new techniques for their assembly and testing of their properties must be created. Controllable nanofabrication methods are of increasing importance across a wide field of electronics in everything from energy efficient LEDs in flat-screen monitors to transistors for ultra-powerful computers. Our process presents a novel method for producing high quality nanoscale carbon nanotube based transistors. These methods will be of the utmost importance in the forthcoming nano-revolution.

Applications


  • Produce flawless carbon nanotubes
  • Identify, select, and position nanotubes with precision
  • Room temperature operation
  • High sensitivity
  • High resolution

Advantages


  • Single electron transistor (SET) nanoscale imaging
  • Novel nano-electromechanical devices

Technology's Essence


The principle behind this technology is two-fold: 1) Synthesis and selection method of flawless carbon nanotubes, and 2) their combination with nanoscale electric circuitry to form fully controlled composite nanoscale electronic device.
Selection of the carbon nanotube(s) is assisted by a scanning probe microscope (SPM). A composite electronic device is assembled from two separated chips; a nanotube chip where nanotubes are grown over wide trenches, and a standard circuit chip with electrode contacts surrounding the gates to be measured. The nano-assembly is achieved by inserting an SPM cantilever into a trench on the nanotube chip and placing the circuit chip over a suitable nanotube. Once in place, the nanotube is cut locally by passing a strong current between the electrode contacts, and the composite chip is formed.
This composite electronic device can be used to map electronic potentials with high resolution of 100 nm, high sensitivity of 1microV/Hz1/2, at frequencies of 100 MHz and more and all this at room temperature.

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  • Prof. Shahal Ilani
1753
The Chiral Induced Spin Selectivity (CISS) effect, discovered in recent years by Prof. Ron Naaman from the Weizmann Institute of Science, implies that electrons transferred through chiral molecules possess a specific spin orientation. Hence, the molecular chirality and electron spin are correlated.A...

The Chiral Induced Spin Selectivity (CISS) effect, discovered in recent years by Prof. Ron Naaman from the Weizmann Institute of Science, implies that electrons transferred through chiral molecules possess a specific spin orientation. Hence, the molecular chirality and electron spin are correlated.
A team of researchers lead by Prof. Naaman have been investigating the CISS effect in different systems. They found that the high efficiency of many natural multiple electron reactions can also be attributed to spin alignment of the electrons involved.
The present innovation looks at hydrogen production through water electrolysis, showing that when using anodes coated by chiral molecules the efficiency of the electrolysis process increases by 30% compared to using uncoated, regular electrodes.

Applications


  • Control of electron spin
  • Significant reduction of over-potential in spin sensitive electrochemical reactions
  • Efficient electrochemical processes
  • Minimum side reactions

  • Advantages


     

    Technology's Essence


    Spin selective electrodes made from standard electrode material are coated with chiral molecules. These coated electrodes were used for electrolysis of water and showed superior efficacy compared to standard un-coated electrodes, by reduction of the over-potential required for the process. This is explained by the spin selective electron conduction through the chiral layer:

     

     

     

    Hydrogen production as a function of time for (A) the chiral molecules and (B) for the achiral molecules. The potentials in the brackets refer to the over-potential compared to DNA coated electrode. The measurements were conducted at the Eapp for each of the molecules.

     

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    • Prof. Ron Naaman
    1670
    A method for selective extraction of precious and rare metals has been developed at the Weizmann Institute. This method allows the efficient and environmentally benign recovery of precious materials that are currently discarded of in large quantities from spent catalysts (automotive and industrial)...

    A method for selective extraction of precious and rare metals has been developed at the Weizmann Institute. This method allows the efficient and environmentally benign recovery of precious materials that are currently discarded of in large quantities from spent catalysts (automotive and industrial) from industrial processes (particularly in the electronic industry).

    Prof. Igor Lubomirsky’s novel process is based on volatilization for selective extraction of precious and rare metals using benign metal salts, rather than dangerous chlorine gas as a chlorinating agent. The new process requires relatively low temperatures and is free from hazardous waste, among its additional advantages over conventional methods.

    We believe that this efficient technology is key to increased reclaimed precious metals output, potentially resulting in the reduction of the demand for primary rare metals.

    Applications


    ·           Recycling precious metals from spent items, e.g. platinum group metals from catalytic convertors


    Advantages


    ·         No toxic input – chlorides are used rather than chlorine gas.

    ·         No hazardous waste is generated in the process.

    ·         Mild conditions. High-temperature furnaces and equipment are not required.

    ·         Relatively simple setup in comparison to conventional ones.

    ·         Small scale plants are economically viable.


    Technology's Essence


    Prof. Igor Lubomirsky and his group developed a novel method for the recovery of PGM from spent catalysts that can be applicable for other spent systems as well.

    The method comprises of crushing the spent catalyst to obtain a catalyst particulate material with g a predetermined grain size and reacting it with chlorine containing salts rather than pure chlorine gas in a furnace at relatively low temperatures (900oC, far below the temperature required in the conventional volatilization method). This is followed by cooling the volatile PMG chloride product converting it into solid phase metal.

     

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    • Prof. Igor Lubomirsky
    • Prof. Igor Lubomirsky
    1715
    Preparation of Re-doped inorganic MoS2 nanoparticles with good sodium ion reversible intercalation properties, to be used as cathode material for next generation sodium ion batteries. Lithium ion batteries (LIB) are currently the leading energy storage solution used in many applications. But lithium is...

    Preparation of Re-doped inorganic MoS2 nanoparticles with good sodium ion reversible intercalation properties, to be used as cathode material for next generation sodium ion batteries.
    Lithium ion batteries (LIB) are currently the leading energy storage solution used in many applications. But lithium is both toxic and limited in quantity (hence expensive) and cannot supply the growing demand for energy storage units as well as the need for cleaner and safer technologies.
    Sodium ion batteries (SIB) are attractive new generation batteries as they incorporate the much less toxic and much more abundant sodium ion.
    Our novel nanoparticles were shown to have competitive electrochemical performances with specific capacity of about 130 mAh/g at 2C and 74 mAh/g at high discharge rate of 20C.

    Applications


    • Electrode material for sodium ion batteries
    • Possible applications in magnesium ion batteries

    Advantages


    • Competitive specific capacity
    • Improved electrical conductivity towards Na ions

    Technology's Essence


    The cathode material's reversible intercalation capacity plays a significant role in determining the total capacity of an energy cell. Intercalation requires entering of ions into the electrode material through diffusion channels.
    The faceted structure of inorganic nanoparticles (IF) induces intrinsic dislocations and stacking faults which serve as ion diffusion channels. Doping of the nanoparticles increases both conductivity, due to n-type doping of the Mo metal, and the number of structural defects (hence diffusion channels), resulting in total increased electrical conductivity.
    The synthetic procedure for producing Re-doped MoS2 nanoparticles is straightforward, based on known and published protocols.

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    • Prof. Reshef Tenne
    1722
    Our technology provides a new type of oxidative cleavage reaction of organic compounds with highly selective product formation.Polyoxometalate (POM) catalysts have become well-known for their utility and diversity in specific reactions. Through the elucidation of POM catalytic pathways, greater...

    Our technology provides a new type of oxidative cleavage reaction of organic compounds with highly selective product formation.
    Polyoxometalate (POM) catalysts have become well-known for their utility and diversity in specific reactions. Through the elucidation of POM catalytic pathways, greater versatility has been achieved. This technology is one such application of a novel POM catalyst and is exploited to cleave carbon-carbon double bonds in alkenes (olefins) through an aerobic oxidation reaction. Oxidation reactions are of particular interest because they are difficult to achieve on an industrial scale while maintaining “green” chemistry practices. [1]

    --------------------------------------------------------------------------------
    [1] Green Chem., 2007, 9, 717-730

    Applications


    • As a novel catalyst in industrial organic chemistry processes
    • Sold as a stand-alone catalyst for laboratory or individual use

    Advantages


    • Environmentally friendly oxidation reaction
    • Easy catalyst regeneration

    Technology's Essence


    Our approach is motivated by societal considerations that demand environmentally benign and sustainable solutions for oxidative reactions. As such, we have developed a scheme to react NO2 with a transition-metal-substituted POM which yields a metal-nitro intermediate that is competent for forming the precursors for oxidation with molecular oxygen, O2, to have a final product of ketones and/or aldehydes, and regenerate the POM catalysts.[1]
    This method has preference towards di/tri-substituted alkenes. High yields of ketones or aldehydes have been produced and the POM catalyst is regenerated without further oxidation to carboxylic acids, as is typical with other oxidative catalysts.
    The selective cleavage of carbon-carbon double or triple bonds with metal-nitro or metal-nitrito compound has not been reported. This exciting new discovery could lead to a wide variety of organic reactions not previously possible, along with revolutionary green oxidative chemistry techniques.

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    [1] J. Am. Chem. Soc., 2014, 136(31), pp10941-10948 

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    • Prof. Ronny Neumann
    1749
    Our novel technology provides an inexpensive, safe and clean solution for loading and unloading of hydrogen on demand with high potential hydrogen storage capacity. Hydrogen storage is currently the key hurdle to its utilization as an alternative green fuel. Being the smallest molecule, hydrogen is...

    Our novel technology provides an inexpensive, safe and clean solution for loading and unloading of hydrogen on demand with high potential hydrogen storage capacity.
    Hydrogen storage is currently the key hurdle to its utilization as an alternative green fuel. Being the smallest molecule, hydrogen is highly diffusive and buoyant. Currently, hydrogen is stored physically as a gas, requiring high-pressure tanks, or in liquid form at cryogenic temperatures, both methods require high energy input. Proposed chemical storage systems are based on relatively expensive materials, suffer from poor regeneration after hydrogen release and require elevated temperatures and pressures.
    The presented technology utilizes inexpensive and abundant organic compounds that generate hydrogen gas during a chemical transformation. Hydrogen release and the regeneration of the original compound are performed in mild conditions using the same catalyst. This system is a promising candidate to be the basis of compact and cost-effective chemical hydrogen storage platforms.

    Applications


  • High potential hydrogen storage capacity (6.6 wt%)
  • Inexpensive and readily available hydrogen carriers (aminoalcohols)
  • Relatively mild release and regeneration conditions

  • Advantages


    • Hydrogen-fueled systems, including fuel cells
    • High capacity hydrogen storage systems

    Technology's Essence


    The technology is based on aminoalcohols that are catalytically converted to cyclic dipeptides, while forming hydrogen gas, using a ruthenium pincer catalyst. Peptide hydrogenation, using the same catalyst, regenerates the aminoalcohol. The same method can be applied with diaminoalkanes and alcohols as well.
    The reaction requires a relatively low organic solvent volume, a catalytic amount of base (KOtBu) for the in situ generation of the active catalyst and mild reaction conditions in terms of hydrogen pressure (50 bar) and temperature (~100 oC). Repetitive cycles of the dehydrogenation-hydrogenation reactions can be performed without adding new catalyst, while maintaining high percentages of aminoalcohol conversion.

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    • Prof. David Milstein
    1684
    Gaseous energy sources such as hydrogen and natural gas (predominantly methane) encompass an intrinsic transport problem because of their volatility and flammability. Adsorption of the gas on a solid material (such as MOF) facilitates safe, light and economical transport of the gas. This is especially...

    Gaseous energy sources such as hydrogen and natural gas (predominantly methane) encompass an intrinsic transport problem because of their volatility and flammability. Adsorption of the gas on a solid material (such as MOF) facilitates safe, light and economical transport of the gas. This is especially significant in the huge natural gas (NG) market where solutions are required for storage and transport of the gas whether from NG reservoirs in high pressure giant tanks or as a compact low pressure NG tank for small vehicles and other NG powered devices.
    The invention involves a new method for the formation of uniform metal organic frameworks (MOFs) at quantitative yields and in a controlled manner.
    These MOFs can be tailored to adsorb specific gases for low pressure - high volume storage and transport applications.

    Applications


    • Low pressure – high volume gas storage and transportation
    • Safe storage of toxic or otherwise dangerous gases
    • Low energy solid phase gas separation and purification
    • Production of MOF-based catalysts

    Advantages


    • Uniform crystallite morphology
    • A quantitative process
    • Ability to design and control product structure
    • Control of pore size
    • Single step process
    • No additives

    Technology's Essence


    The invention comprises a new solvothermal synthetic procedure in which specific metal ions are selected to react with specific organic ligands to form uniform sub-microstructured MOFs with a narrow size distribution and without the need for a modulator to define the crystal morphology.
    Controlling the selected reagents as well as the specific reaction conditions influences the resulting crystallites formed and enables a fine selection of the desired structure.
    MOFs prepared this way have exceptional uniformity profiles of size and shape and can be tailored to selectively adsorb specific gases for low pressure - high volume storage and transport applications.

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    • Prof. Milko E. Van der Boom
    1615
    A new process for the production of catalytic metal coated WS2 nanotubes, using cobalt, palladium, nickel, chromium and noble metals.These metal coated nanotubes were shown to have catalytic activity in different organic reactions including degradation of known organic contaminants (Co coated) and...

    A new process for the production of catalytic metal coated WS2 nanotubes, using cobalt, palladium, nickel, chromium and noble metals.
    These metal coated nanotubes were shown to have catalytic activity in different organic reactions including degradation of known organic contaminants (Co coated) and Suzuki and Heck coupling reactions (Pd coated).
    Since catalytic chemical reactions are at the heart of many processes and industries, and efficient catalysis is essential for both economic and environmental reasons, this development of a new catalytic platform bears a potential to influence many diverse markets.

    Applications


    • New and efficient Pd-based catalysts for diverse reactions.
    • New and efficient crude oil HDS catalysts.
    • New and efficient wastewater purification catalysts.
    • Production of activated hybrid WS2 nanotubes with new properties.
    • Tailoring catalytic nanotubes with different band gaps adjusted to different activation and catalysis applications.

    Advantages


    • Formation of highly active catalytic nanotubes
    • Utilization of the nanotubes' very large surface area
    • Recruiting specific nanotube semiconducting characteristics for special catalysis requirements

    Technology's Essence


    The invention involves deposition of metal nanoparticles on prepared WS2 nanotubes (INT-WS2) in a two stage process involving Pd-nanocrystallites assisted activation followed by electroless plating.
    In this process WS2 nanotubes are synthesized according to known procedures. The nanotubes are then covered by metal nanoparticles in a simple and straightforward procedure resulting with highly active nanotubes which can be utilized as catalysts for various chemical reactions.
    This new hybrid technology opens the way to a new family of highly efficient, tunable catalysts; the INTs large surface area, specific band gap design and choice of metal result in an ability to produce unique tailor-made catalysts, applicable to many different industries. 

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    • Prof. Reshef Tenne
    • Prof. Reshef Tenne
    1551
    A novel set of manganese, ruthenium and related borohydride complexes (Pincer-type) were developed as remarkably efficient and environmentally-benign catalysts for the synthesis of alcohols, amines, amides, imines and esters, which are the basic building blocks for the research, chemicals,...

    A novel set of manganese, ruthenium and related borohydride complexes (Pincer-type) were developed as remarkably efficient and environmentally-benign catalysts for the synthesis of alcohols, amines, amides, imines and esters, which are the basic building blocks for the research, chemicals, pharmaceutical and agrochemical industries. In addition, a catalytic carbon-carbon bond formation using non-activated aliphatic nitriles and carbonyl compounds was achieved with the manganese complex. These reactions are conducted under mild and neutral conditions, using low catalyst loading, require no hydrogen acceptors or oxidants, employ no corrosive or toxic reagents and generate no waste. Moreover, manganese is one of the most abundant transition metals on earth crust, making it appealing and biocompatible when considering a system for eventual scale-up and industrial use.

    In view of global concerns regarding economy, environment and sustainable energy resources, there is an urgent need for the discovery of new catalytic reactions. These newly developed catalysts address key problems of current traditional synthetic methodologies, both from the economic and the environmental aspects.

    Applications


    ·         Pharmaceuticals

    ·         Dyes

    ·         Cosmetics and fragrances

    ·         Fibers

    ·         Agrochemicals


    Advantages


    ·         Cost-effective in terms of reagents, reactions conditions (low temperature and pressure) and waste treatment (green reactions).

    ·         New synthetic pathways that were not possible before, such as the synthesis of amides and imines directly from alcohols and amines, esters synthesis from alcohols and methanol synthesis from CO2 and hydrogen.

    ·         Broad substrate scope.

    ·         Excellent yields.


    Technology's Essence


    Prof. David Milstein’s group has discovered a new mode of action for metal-ligand cooperation, involving aromatization–dearomatization of ligands. Pincer-type, pyridine-based complexes of Mn, Ir, Rh, Ru, Pd, Pt and acridine complexes of Ru have been shown to exhibit such cooperation, leading to facile activation of C-H, C-C, H-H, N-H, O-H bonds, and to novel, environmentally friendly reactions catalyzed by Mn and Ru.

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    • Prof. David Milstein
    1644
    Computer memory and storage are among the most critical components of today’s consumer electronics and computer technology. Currently available memory and storage technologies have inherent limitations that confine the capacity and speed of access to memory devices. The present innovation is based on...

    Computer memory and storage are among the most critical components of today’s consumer electronics and computer technology. Currently available memory and storage technologies have inherent limitations that confine the capacity and speed of access to memory devices.

    The present innovation is based on Chiral Induced Spin Selectivity (CISS) effect that was established experimentally and theoretically in the last decade, and allows for production of inexpensive, high-density universal memory-on-chip devices, that don’t require the use of permanent magnets.

    Applications


    ·         Inexpensive, high-density universal memory-on-chip devices

    ·         The technology can be used as superior alternative for both Random Access memory and Flash memory

    ·         Surface-controlled spintronic devices

    ·         Logic and data processing


    Advantages


    ·         Up to 70 times more storage on the same physical size

    ·         Up to 100 times lower energy consumption

    ·         Si-Compatible

    ·         High density (can reach Si technology limit)

    ·         Estimated low cost

    ·         Overcomes limitations of other magnetic-based memory technologies


    Technology's Essence


    Ferromagnets can be magnetized either by external magnetic fields or by spin polarized current. However, the current density required for inducing magnetization is extremely high and significantly affects the device’s structure and performance. The newly discovered CISS effect allows for magnetization switching of Ferromagnets, which is induced solely by adsorption of chiral molecules, where much lower current density is sufficient to induce the magnetization reversal. Chiral Memory technology uses the CISS effect for spin selectivity instead of the common ferromagnetic-based spin filters. This allows, in principle, the memory bit to be miniaturized down to a single magnetic nanoparticle or a nano-scale domain. The operation principle of the device relies on the spin-selective transmission of electrons through organic chiral molecules to the ferromagnetic layer of the device, which results in the magnetization of this layer and efficient storing of bits of information. The magnetization switching by local adsorption of chiral molecules eliminates the need for a permanent magnet.

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    • Prof. Ron Naaman
    1564
    A new recyclable size-selective filtration device. Particle size, chemical purity and dispersion of nanoparticles crucially determine their optical, electronic and chemical properties. Size-selective separation technologies are becoming increasingly important for the development of nanoparticles with...

    A new recyclable size-selective filtration device.

    Particle size, chemical purity and dispersion of nanoparticles crucially determine their optical, electronic and chemical properties. Size-selective separation technologies are becoming increasingly important for the development of nanoparticles with well-defined sizes, which have application in the fields of optoelectronic devices, biomedicine, materials, and catalysis.

    Researchers at the Weizmann Institute have fabricated supramolecular ultrafiltration membranes that can be used for filtration and size-selective chromatography of nanoparticles. The membranes are composed of a self-assembled three-dimensional fibrous network that is held together by reversible non-covalent interactions.

    The membranes are robust, easy to fabricate, and recyclable.

    Applications


    • Size-selective separation of semiconductor and metal nanoparticles
    • Uniformity and monodispersity of nanoparticles in solution.
    • Size exclusion chromatography of nanoparticles in the sub-5-nm size regime.

    Advantages


    • Efficient and inexpensive

    • Fast and easy fabrication

    • Recyclable

    • Self-assembled

    • Dual application regime: filtration and/or chromatography


    Technology's Essence


    The recyclable supramolecular membranes are formed from unique perylene derivatives that are large and flat aromatic molecules. These molecules are insoluble in water and form a 3-D network over a solid support, which can be used for the separation of nanoparticles.

    The filters can be subsequently recycled from this mixture using an organic solvent (e.g. dichloromethane), which separates the membrane material from the water-soluble nanoparticles, and reused without loss of performance.

    This material is hence highly attractive for application in the field of nanotechnology.

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    • Dr. Boris Rybtchinski

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