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[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]

New catalyst supports ultra-low-temperature water-gas-shift reaction for hydrogen production

July 06, 2017

Researchers from China and the US have synthesized gold layered clusters on an α-MoC substrate to create an interfacial catalyst system for the ultra-low-temperature water-gas shift (WGS) reaction for the production of high-purity hydrogen and concomitant utilization of carbon monoxide (CO). The discovery, described in a paper in the journal Science, could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

In the work described in the paper, water was activated over α-MoC at 303 K (30 ˚C), while the CO adsorbed on adjacent Au sites reacted with surface hydroxyl groups formed from water splitting, leading to a high WGS activity at low-temperatures.

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U Minn seeking to license new process to produce isoprene from biomass at high yield; green tires

July 02, 2017

Researchers from the University of Minnesota, with colleagues at the University of Massachusetts Amherst, have developed a new high-yield process—a hybrid of fermentation followed by thermochemical catalysis—to produce renewable isoprene from biomass.

In the process, fermentation of sugars produces itaconic acid, which undergoes catalytic hydrogenation to produce 3-methyltetrahydrofuran (MTHF). The MTHF then undergoes catalytic dehydra-decyclization to isoprene. This catalytic process dehydrates MTHF to isoprene via several combinations of temperatures, pressures, and space velocities (reactant volumetric flow rate per volume of catalyst) and achieves selectivity of MTHF to isoprene.

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Durable ruthenium and graphene fuel cell catalyst matches performance of platinum alloys

June 30, 2017

Scientists at Rice University and their colleagues in China have fabricated a durable catalyst for high-performance fuel cells by attaching single ruthenium atoms to nitrogen-doped graphene. Catalysts that drive the oxygen reduction reaction in fuel cells are usually made of platinum. Platinum is expensive, however, and scientists have searched for decades for a suitable replacement.

The ruthenium-graphene combination may fit the bill, said chemist James Tour, whose lab developed the material with his colleagues at Rice and in China. The Ru/nitrogen- doped GO catalyst exhibits excellent four-electron ORR activity, offering onset and half-wave potentials of 0.89 and 0.75 V, respectively, vs a reversible hydrogen electrode (RHE) in 0.1 M HClO4, together with better durability and tolerance toward methanol and carbon monoxide poisoning than seen in commercial Pt/C catalysts. A paper on the work appears in the journal ACS Nano.

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Osaka team develops new solar-to-hydrogen catalyst that uses broader spectrum of light

June 26, 2017

A team at Osaka University in Japan has developed a new material based on gold and black phosphorus to harvest a broader spectrum of sunlight for water-splitting to produce hydrogen.

The three-part composite maximizes both absorbing light and its efficiency for water splitting. The core is a traditional semiconductor—lanthanum titanium oxide (LTO). The LTO surface is partly coated with gold nanoparticles. Finally, the gold-covered LTO is mixed with ultrathin sheets of the element black phosphorus (BP), which acts as a light absorber. The optimum H2 production rates of BP-Au/LTO were about 0.74 and 0.30 mmol g-1 h-1 at wavelengths longer than 420 nm and 780 nm, respectively. A paper on the team’s work is published in the journal Angewandte Chemie: International Edition.

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Kyushu team develops multifunctional catalyst for poison-resistant hydrogen fuel cells; both H2 and CO as fuel

June 25, 2017

Researchers at Kyushu University, Japan, have developed the first catalyst that can oxidize both hydrogen and carbon monoxide, depending on the pH of the reaction system. Carbon monoxide is a common pollutant in commercially available hydrogen gas but it poisons the platinum catalysts used in today’s fuel cells. A paper on the work appears in the journal Angewandte Chemie International Edition.

The new catalyst, based on a nickel-iridium [NiIr] complex, mimics the behavior of two enzymes: hydrogenase in acidic media (pH 4-7) and carbon monoxide dehydrogenase in basic media (pH 7-10). The team, led by Prof. Seiji Ogo, constructed a proof-of-concept fuel cell that turned the tables on carbon monoxide poisoning by using it as a fuel and generated energy from a 1:1 mixture of the two gases.

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New efficient, low-temperature catalyst for converting water and CO to hydrogen and CO2

June 24, 2017

Scientists in the US and China have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO) via the water-gas shift (WGS) reaction. The discovery—described in a paper in the journal Science—could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

The WGS reaction (CO+H2O = H2+CO2) is an essential process for hydrogen generation and CO removal in various energy-related chemical operations. The reaction is favored at a low working temperature. Application in fuel cells requires a WGS catalyst to be highly active, stable and energy-efficient and match the working temperature of on-site hydrogen generation and consumption units.

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DOE awarding $2M to CMU-led project to develop PGM-free cathodes for fuel cells

June 21, 2017

The US Department of Energy is awarding roughly $15.8 million for 30 projects working toward the discovery and development of innovative, low-cost materials needed for hydrogen production and storage and for automotive fuel cells (earlier post).

Of those 30 projects, Carnegie Mellon University Mechanical Engineering Associate Professor Shawn Litster has been selected to receive $2 million in funding as principal investigator of his multi-institution team’s research project, “Advanced PGM-free Cathode Engineering for Higher Power Density and Durability.”

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Stanford team develops copper catalyst for increased selectivity of production of ethanol via electroreduction of CO2

Researchers at Standford University have designed large-format, thin-film copper catalysts for the electroreduction of CO2 to ethanol. The results are published in Proceedings of the National Academy of Sciences.

“One of our long-range goals is to produce renewable ethanol in a way that doesn’t impact the global food supply. Copper is one of the few catalysts that can produce ethanol at room temperature,” he said. “You just feed it electricity, water and carbon dioxide, and it makes ethanol. The problem is that it also makes 15 other compounds simultaneously, including lower-value products like methane and carbon monoxide. Separating those products would be an expensive process and require a lot of energy,” said study principal investigator Thomas Jaramillo, an associate professor of chemical engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory.

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Molybdenum coating improves the efficiency of water-splitting catalysts for producing hydrogen

June 12, 2017

Researchers at KAUST have developed a novel molybdenum-coated catalyst that can efficiently split water in acidic electrolytes and that could help with the efficient production of hydrogen.

Scientists are searching for ways of improving the water-splitting reaction by developing an optimal catalyst. While many different materials have been tried, they are usually adversely affected by the oxygen that is also created alongside the hydrogen during the process. The two gaseous products can easily recombine back to water due to reverse water-forming reactions, hindering the production of hydrogen.

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EPFL team develops low-cost catalyst for splitting CO2

June 07, 2017

EPFL scientists have developed an Earth-abundant and low-cost catalytic system for splitting CO2 into CO and oxygen—an important step towards achieving the conversion of renewable energy into hydrocarbon fuels. A solar-driven system set up using this catalyst was able to split CO2 with an efficiency of 13.4%. A paper on the work appears in the journal Nature Energy.

The research was carried out by the lab of Michael Grätzel at EPFL. Grätzel is known worldwide for the invention of dye-sensitized solar cells (“Grätzel cells”). The new catalyst, developed by PhD student Marcel Schreier, postdoc Jingshan Luo, and several co-workers, is made by the atomic layer deposition (ALD) of tin oxide (SnO2) on copper oxide (CuO) nanowires. Tin oxide suppresses the generation of side-products, which are commonly observed from copper oxide catalysts, leading to the sole production of CO in the electroreduction of CO2.

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UNSW Sydney team develops inexpensive water-splitting catalyst using 2D MOF framework array

June 06, 2017

UNSW Sydney chemists have fabricated a new, inexpensive catalyst for water splitting based on an ultrathin nanosheet array of metal-organic frameworks (MOFs) on different substrates.

Their nickel-iron-based metal-organic framework array (NiFe-MOF) demonstrates superior electrocatalytic performance towards the oxygen evolution reaction (OER) with a small overpotential of 240 mV at 10 mA cm−2 and operates for 20,000 s with no detectable activity decay. The turnover frequency of the electrode is 3.8 s−1 at an overpotential of 400 mV. An open-access paper on their work is published in Nature Communications.

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BNL, VT team creates Ru,Rh supramolecular photocatalysts for enhanced hydrogen production via artificial photosynthesis

June 04, 2017

Scientists have been trying to artificially replicate photosynthesis to convert solar energy to stored chemical energy, with the objective of producing environmentally friendly and sustainable fuels, such as hydrogen and methanol. However, mimicking key functions of the photosynthetic center, where specialized biomolecules carry out photosynthesis, has proven challenging. Artificial photosynthesis requires a molecular system that can absorb light; transport and separate electrical charge; and catalyze fuel-producing reactions. These complicated processes must operate synchronously to achieve high energy-conversion efficiency.

Now, chemists from the US Department of Energy’s (DOE) Brookhaven National Laboratory (BNL) and Virginia Tech have designed two supramolecular photocatalysts that incorporate individual components specialized for light absorption, charge separation, or catalysis. In both molecular systems, multiple light-harvesting centers made of ruthenium (Ru) metal ions are connected to a single catalytic center made of rhodium (Rh) metal ions through a bridging molecule that promotes electron transfer from the Ru centers to the Rh catalyst, where hydrogen is produced. A paper on the work is published in the Journal of the American Chemical Society.

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New composite reduces rare earth element usage in three-way catalytic converters

June 02, 2017

The high-performance, three-way catalytic (TWC) converter is one of the workhorses of emissions reduction for gasoline engines. The TWC reduces NOx to nitrogen and oxygen; oxidizes CO to CO2, and oxidizes unburnt hydrocarbons to carbon CO2 and water. However, TWCs require the use of the rare-earth element Cerium (Ce), which is increasing in price and can suffer from supply problems.

Now, researchers at Kumamoto University in Japan, led by Professor Masato Machida, have developed a new composite material—a CeO2-grafted MnFeOy (CeO2/MnFeOy) as a substitute for the conventional CeO2 material in three-way catalysts. A paper on their work is published in the ACS journal Industrial & Engineering Chemistry Research.

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Penn State, FSU team develops low-cost, efficient layered heterostructure catalyst for water-splitting

A team of scientists from Penn State and Florida State University have developed a lower cost and industrially scalable catalyst consisting of synthesized stacked graphene and WxMo1–xS2 alloy phases that produces pure hydrogen through a low-energy water-splitting process.

The results of their study, published in the journal ACS Nano, indicate that heterostructures formed by graphene and W0.4Mo0.6S2 alloys are far more efficient than WS2 and MoS2 by at least a factor of 2, and they are superior compared to other reported transition-metal dichalcogenide (TMD) systems. The researchers suggested that their strategy offers a cheap and low temperature synthesis alternative able to replace Pt in the hydrogen evolution reaction (HER).

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Argonne researchers make vanadium into a useful low-cost catalyst for hydrogenation

May 28, 2017

Researchers at the US Department of Energy’s Argonne National Laboratory have developed an unusually active form of vanadium for hydrogenation reactions. Vanadium is an inexpensive common metal that could replace some of the precious metals currently found in catalysts used in these reactions, frequently used in processing of fuels (petro- and drop-in bio-) and petrochemicals.

The vanadium catalyst exhibits unprecedented reactivity in liquid- and gas- phase alkene/alkyne hydrogenation. Catalyst poisoning experiments revealed that 100% of the V sites are active for hydrogenation. A paper on their work is published in the RSC journal Chemical Communications.

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Bochum chemists develop method to produce self-healing catalyst films for hydrogen production

May 27, 2017

Chemically aggressive conditions prevail during the electrochemical splitting of water to produce hydrogen, wearing out the catalysts used. Further, engineering stable electrodes using highly active catalyst nanopowders for electrochemical water splitting remains a notorious challenge.

Now, chemists at the Centre for Electrochemical Sciences at Ruhr-Universität Bochum (RUB) have devised an innovative and general approach for attaining highly stable catalyst films with self-healing capability based on in-situ self-assembly of catalyst particles during electrolysis. A team comprising Stefan Barwe, Prof Dr Wolfgang Schuhmann and Dr Edgar Ventosa from the Bochum Chair of Analytical Chemistry reports on this in the journal Angewandte Chemie International Edition. The work took place as part of the cluster of excellence Resolv.

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Platinum-yttrium nanoalloys 10x as effective as platinum nanoparticles in fuel cells

May 25, 2017

Researchers from Chalmers University of Technology and Technical University of Denmark have shown that thin alloy films of single-target co-sputtered platinum-yttrium exhibit up to 7x higher specific activity (13.4 ± 0.4 mA cm−2) for the oxygen reduction reaction (ORR) in fuel cells than polycrystalline platinum, and up to one order of magnitude higher mass activity (3.5 ± 0.3 A mg−1) than platinum nanoparticles.

These nanoalloys have the highest reported ORR activity for an as-deposited material—i.e., without any additional chemical or thermal treatment. The films also show an improvement in stability over the same materials in nanoparticulate form. In a paper published in the journal Advanced Materials Interfaces, the researchers suggest that their results open new possibilities for the preparation of platinum-rare earth metal alloy catalysts in commercial devices.

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New mesocrystal photocatalyst enhances light-driven hydrogen production

May 18, 2017

A group of Japanese researchers has developed a novel photocatalyst for increased hydrogen production. The strontium titanate mesocrystal exhibits three times the efficiency for hydrogen evolution compared to conventional disordered systems in alkaline aqueous solution. The mesocrystal also exhibits a high quantum yield of 6.7% at 360 nm in overall water splitting and even good durability up to 1 day.

The discovery was made by a joint research team led by Associate Professor Takashi Tachikawa (Molecular Photoscience Research Center, Kobe University) and Professor Tetsuro Majima (Institute of Scientific and Industrial Research, Osaka University). Their findings were published in the journal Angewandte Chemie International Edition.

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UH team develops new, highly efficient and durable OER catalyst for water splitting

May 16, 2017

Researchers at the University of Houston have developed a catalyst—composed of easily available, low-cost materials and operating far more efficiently than previous catalyst—that can split water into hydrogen and oxygen.

The robust oxygen-evolving electrocatalyst consists of ferrous metaphosphate on self-supported conductive nickel foam that is commercially available in large scale. The catalyst yields current densities of 10 mA/cm2 at an overpotential of 177 mV, 500 mA/cm2 at only 265 mV, and 1,705 mA/cm2 at 300 mV, with high durability in alkaline electrolyte of 1 M KOH even after 10,000 cycles. This represents an activity enhancement by a factor of 49 in boosting water oxidation at 300 mV relative to the state-of-the-art IrO2 catalyst. A paper on their work is published in Proceedings of the National Academy of Sciences (PNAS).

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Brookhaven team identifies active sites on catalysts for converting CO2 to methanol

May 10, 2017

Chemists from the US Department of Energy’s Brookhaven National Laboratory and their collaborators have definitively identified the active sites of a catalyst commonly used for making methanol from CO2. The results, published in the journal Science, resolve a longstanding debate about exactly which catalytic components take part in the chemical reactions—and thus which should be the focus of efforts to boost performance.

The hydrogenation of carbon dioxide is a key step in the production of methanol; catalysts made from copper (Cu) and zinc oxide (ZnO) on alumina supports are often used.

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Ames Lab, Iowa State team develops more efficient catalytic material for fuel cell applications

May 09, 2017

Researchers at the US Department of Energy’s (DOE’s) Ames Laboratory have discovered a method for making smaller, more efficient intermetallic nanoparticles for fuel cell applications, and which also use less of the expensive precious metal platinum. A paper on the work is published in the Journal of the American Chemical Society.

The researchers succeeded by overcoming some of the technical challenges presented in the fabrication of the platinum-zinc nanoparticles with an ordered lattice structure, which function best at the small sizes in which the chemically reactive surface area is highest in proportion to the particle volume.

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New molybdenum-coated catalyst produces hydrogen from water-splitting more efficiently; preventing the back reaction

May 07, 2017

Water-splitting systems require a very efficient catalyst to speed up the chemical reaction that splits water into hydrogen and oxygen, while preventing the two gases from recombining back into water. Now an international research team has developed a new catalyst with a molybdenum (Mo) coating that prevents this problematic back reaction and works well in realistic operating conditions.

The research team included scientists from the Department of Energy’s SLAC National Accelerator Laboratory, King Abdullah University of Science and Technology, Fukuoka University, University of Tokyo, and the Center for High Pressure Science and Technology Advanced Research in Shanghai, China. The work was supported by King Abdullah University of Science and Technology. A paper on the work is published in the journal Angewandte Chemie.

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China team develops efficient multifunctional catalyst for conversion of CO2 to gasoline-range hydrocarbons

May 02, 2017

A research team led by Dr. Jian Sun and Prof. Qingjie Ge at the Dalian Institute of Chemical Physics in China has developed an efficient, stable, and multifunctional Na-Fe3O4/HZSM-5 catalyst for the direct production of gasoline-range hydrocarbons from CO2 hydrogenation. This catalyst exhibited 78% selectivity to C5-C11 as well as low (4%) CH4 at a CO2 conversion of 22% under industrial relevant conditions.

The gasoline fractions are mainly isoparaffins and aromatics, thus favoring the octane number. Moreover, the multifunctional catalyst exhibited a remarkable stability for 1,000 h on stream, showing potential to be a promising industrial catalyst for CO2 conversion to liquid fuels. An open-access paper on their work is published in the journal Nature Communications.

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KAUST team alters atomic composition of MoS2 to boost performance as water-splitting catalyst for H2 production

April 13, 2017

Researchers at KAUST have developed and used a novel way of increasing the chemical reactivity of a two-dimensional molybdenum disulfide material to produce a cheap and effective catalyst for water splitting to produce hydrogen. This technique may also have potential benefits for other manufacturing industries.

One route to hydrogen generation is by electrolysis: passing an electrical current through water via two electrodes to cause a chemical reaction that breaks the water molecule into its component hydrogen and oxygen atoms. The speed of this hydrogen evolution reaction can be increased using a catalyst on the electrodes. Platinum is a perfect material for the job, but is it very expensive.

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Elemental boron effective photothermocatalyst for the conversion of CO2 for fuels and chemicals

April 11, 2017

Researchers in Japan and China developed an efficient method for CO2 reduction over elemental boron catalysts in the presence of only water and light irradiation through a photothermocatalytic process. This could form the basis of a new, more efficient process for converting the greenhouse gas CO2 into a useful carbon source for the production of fuels and chemical products.

The “self-heating” boron catalyst makes particularly efficient use of sunlight to reduce CO2, serving as a light harvester, photothermal converter, hydrogen generator, and catalyst in one. A paper on their work is published in the journal Angewandte Chemie.

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Renewable plastic precursor could reduce cost of cellulosic ethanol by >$2/gallon

April 10, 2017

A team of chemical and biological engineers at the University of Wisconsin–Madison has developed a new chemical pathway a way to produce from biomass a valuable compound—1,5-pentanediol, a plastic precursor primarily used to make polyurethanes and polyester plastics—that they estimate could lower the cost of cellulosic ethanol by more than two dollars per gallon.

The highly efficient approach devised by Professor George Huber and collaborators is much cheaper than a previously reported method—direct hydrogenolysis of tetrahydrofurfuryl alcohol (THFA)—and represents the first economically viable way of producing 1,5-pentanediol from biomass. A paper on their work is published in the journal ChemSusChem.

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China team develops highly efficient catalyst for low-temperature aqueous phase refoming of methanol to produce hydrogen

April 01, 2017

Researchers in China, along with colleagues in the US, have developed a new catalyst that shows outstanding hydrogen-production activity and stability in the low-temperature aqueous phase reforming of methanol (APRM).

In a paper in the journal Nature, the team reports that platinum (Pt) atomically dispersed on α-molybdenum carbide (α-MoC) enables low-temperature (150–190 ˚C), base-free hydrogen production through APRM, with an average turnover frequency reaching 18,046 moles of hydrogen per mole of platinum per hour. The new catalyst, the researchers suggest, paves a way towards a commercially achievable hydrogen-storage strategy.

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Aalto University team develops promising new electrocatalyst for hydrogen evolution reaction; one-hundredth the amount of Pt

March 26, 2017

A group of Aalto University (Finland) researchers led by professors Tanja Kallio and Kari Laasonen has developed a manufacturing method for hydrogen evolution reaction (HER) electrocatalysts that use only one-hundredth of the amount of platinum generally used in commercial products.

They achieved pseudo atomic-scale dispersion of Pt—i.e. individual atoms or sub-nanometer clusters—on the sidewalls of single-walled carbon nanotubes (SWNTs) with a simple and readily up-scalable electroplating deposition method. These SWNTs activated with an ultra-low amount of Pt exhibit a similar activity to that of a commercial Pt/C with a notable higher (~66-333 fold) Pt loading for catalyzing hydrogen evolution reaction (HER) under the acidic conditions required in proton exchange membrane technology. A paper on their work is published in the journal ACS Catalysis.

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Researchers create efficient, simple-to-manufacture photoanode for solar water-splitting

March 24, 2017

Researchers at Rice University and the University of Houston created an efficient, simple-to-manufacture core/shell photoanode with a highly active oxygen evolution electrocatalyst shell (FeMnP) and semiconductor core (rutile TiO2) for the photoelectrochemical oxygen evolution reaction (PEC-OER) for solar water splitting.

The lab of Kenton Whitmire, a Rice professor of chemistry, teamed up with researchers at the University of Houston and discovered that growing a layer of an active catalyst directly on the surface of a light-absorbing nanorod array produced an artificial photosynthesis material that could split water at the full theoretical potential of the light-absorbing semiconductor with sunlight. The results appear in two new studies. The first, on the creation of the catalytic films, appears in Chemistry: A European Journal. The second, which details the creation of photoanodes, appears in ACS Nano.

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Cambridge team demonstrates light-driven photoreforming of unprocessed biomass to H2 at room temperature

March 14, 2017

A team of scientists at the University of Cambridge has reported the light-driven photoreforming of cellulose, hemicellulose and lignin to H2 using semiconducting cadmium sulfide quantum dots in alkaline aqueous solution.

The system operates under visible light, is stable beyond six days and is even able to reform unprocessed lignocellulose, such as wood and paper, under solar irradiation at room temperature, presenting an inexpensive route to drive aqueous proton reduction to H2 through waste biomass oxidation. A paper on their work is published in the journal Nature Energy.

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IU team creates efficient nanographene-Re electro- and photo-catalyst for efficient reduction of CO2 to CO

March 09, 2017

Researchers at Indiana University Bloomington have synthesized a nanographene–Re (Rhenium) complex that functions as an efficient electrocatalyst and photocatalyst for the selective reduction of CO2 to CO for subsequent conversion to fuels.

The complex can selectively electrocatalyze CO2 reduction to CO in tetrahydrofuran at −0.48 V vs NHE—the least negative potential reported for a molecular catalyst. In addition, the complex can absorb a significant spectrum of visible light to photo-catalyze the chemical transformation without the need for a photo-sensitizer. A report on their work is published in the Journal of the American Chemical Society.

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Texas A&M team developing photocatalyst to turn CO2 into renewable hydrocarbon fuels

March 06, 2017

Researchers with the Department of Mechanical Engineering at Texas A&M University, led by Dr. Ying Li, associate professor of mechanical engineering, are developing a photocatalyst to convert CO2 into renewable hydrocarbon fuels. The photocatalyst material acts as a semiconductor, absorbing the sunlight which excites the electrons in the semiconductor and gives them the electric potential to reduce water and CO2 into carbon monoxide and hydrogen, which together can be converted to liquid hydrocarbon fuels, said Li.

The first step of the process involves capturing CO2 from emissions sources. The material, which is a hybrid of titanium oxide and magnesium oxide, uses the magnesium oxide to absorb the CO2 and the titanium oxide to act as the photocatalyst.

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Light over heat: UV-driven rhodium nanoparticles catalyze conversion of CO2 to methane

February 27, 2017

Duke University researchers have engineered rhodium nanoparticles that can harness the energy in ultraviolet light and use it to catalyze the conversion of carbon dioxide to methane, a key building block for many types of fuels. An open-access paper on the work is published in Nature Communications.

Industrial-scale catalysis for fuels and materials generally relies upon heated catalysts for heterogeneous catalytic reactions with large activation energies. Such catalytic processes demand high energy inputs, shorten catalyst lifetimes through sintering deterioration and require product selectivity to mitigate unfavorable side reactions. Researchers have recently discovered that plasmonic metal nanoparticles are photocatalytically active, and that product selectivity may be achieved by tuning photon and LSPR (localized surface plasmon resonances) energies.

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Toyota’s new three-way catalyst reduces precious metal usage by 20%; improving uniformity of flow with FLAD

February 22, 2017

Toyota Motor Corporation announced the commercial availability of a new, smaller three-way catalyst for the treatment of NOx, CO and unburned hydrocarbons from gasoline engines that uses 20% less precious metal in approximately 20% less volume, while maintaining the same exhaust gas purification performance.

The catalyst uses the world’s first integrally-molded Flow Adjustable Design Cell (FLAD) substrate. FLAD features a different cell cross-sectional area at the inner portion compared to that at the outer portion. Innovative design and manufacturing technologies have allowed for the mass production of the new catalyst, which will gradually be installed in new vehicle models, starting with the Lexus LC 500h later this year.

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PNNL team develops fastest synthetic catalyst for H2 production; controlling structural dynamics for 1,000x performance boost

February 06, 2017

Using a natural catalyst from bacteria for inspiration, researchers at Pacific Northwest National Laboratory (PNNL) have now developed the fastest synthetic catalyst for hydrogen production—producing 45 million molecules per second—by controlling the structural dynamics of the molecular catalyst. Instead of a costly metal such as platinum, this catalyst uses inexpensive, abundant nickel at its core.

Although the catalyst requires more energy to run than a conventional platinum catalyst, the insight garnered from this result might eventually help make hydrogen fuel in an environmentally friendly, affordable way, the researchers report in the chemistry journal Angewandte Chemie International Edition.

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UNIST team boosts performance of perovskite catalyst for metal-air batteries & fuel cells using polypyrrole

January 24, 2017

A team of researchers from S. Korea’s UNIST, with colleagues from Northwestern University, have successfully developed a new way to increase the activity of perovskite oxide catalysts for the oxygen reduction reaction (ORR) and/or the oxygen evolution reaction (OER) in rechargeable metal-air batteries and fuel cells simply by adding the conductive polymer polypyrrole. A paper on their work was published in the RSC journal Energy & Environmental Science.

Oxygen-related electrochemistry is important in next-generation energy conversion and storage. The oxygen reduction reaction (ORR) is the cathodic process of fuel cells and metal air batteries for generating electricity; the reverse, the oxygen evolution reaction (OER), is the anodic processes for splitting water and charging metal air batteries.

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POSTECH, Hyundai team develops new more thermally robust catalyst for NOx reduction with diesel engines

January 23, 2017

A team from Pohang University of Science and Technology (POSTECH) in S. Korea, with colleagues from Hyundai Motors’s R&D group and the University of St. Andrews in the UK has developed a new, more thermally robust catalyst for NOx aftertreatment systems for diesel engines. A paper on their work is published in the journal Angewandte Chemie International Edition.

The catalyst—divalent copper ions fully exchanged into high-silica LTA zeolites(Cu-LTA)—demonstrated excellent maintenance of activity for NOx reduction with NH3 under vehicle-simulated conditions even after hydrothermal aging at 900 °C, a critical temperature that the current commercial Cu-SSZ-13 catalyst cannot overcome owing to thermal deactivation.

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NREL shows graded catalytic-protective layer boosts longevity of high-efficiency photocathodes for renewable hydrogen

January 09, 2017

Researchers at the US Department of Energy’s National Renewable Energy Laboratory (NREL) have developed a method which boosts the longevity of high-efficiency photocathodes in photoelectrochemical water-splitting devices. Their works demonstrates the potential of utilizing a hybridized, heterogeneous surface layer as a cost-effective catalytic and protective interface for solar hydrogen production.

In a paper published in the journal Nature Energy, they show that annealing a bilayer of amorphous titanium dioxide (TiOx) and molybdenum sulfide (MoSx) deposited onto GaInP2 results in a photocathode with high catalytic activity and stability for the hydrogen evolution reaction. The study showed that the annealing results in a graded MoSx/MoOx/TiO2 layer that retains much of the high catalytic activity of amorphous MoSx but with stability similar to crystalline MoS2.

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Researchers demonstrate new nickel selenide catalyst for more efficient water splitting

December 19, 2016

A team of researchers from Missouri University of Science and Technology and National and Kapodistrian University of Athens in Greece have developed a highly efficient transition metal selenide-based coordination complex, [Ni{(SePiPr2)2N}2] for oxygen evolution and hydrogen evolution reactions (OER and HER, respectively) in alkaline solution.

In a paper published in ChemSusChem describing their work, the researchers reported that very low overpotentials of 200 mV and 310 mV were required to achieve 10 mA cm−2 for OER and HER, respectively. The overpotential for OER is one of the lowest that has been reported up to now, making this one of the best OER electrocatalysts. In addition, this molecular complex exhibits an exceptionally high mass activity (111.02 A g−1) and a much higher turnover frequency (TOF) value (0.26 s−1) at a overpotential of 300 mV. The bifunctional electrocatalyst enables water electrolysis in alkaline solutions at a cell voltage of 1.54 V.

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Efficient and stable PtPb/Pt core/shell nanoplate catalysts for ORR in fuel cells; new way of introducing tensile strain

Scientists from the US Department of Energy’s (DOE) Brookhaven National Laboratory; California State University–Northridge; Soochow University; Peking University; and Shanghai Institute of Applied Physics have developed new catalysts for the oxygen reduction reaction (ORR) in fuel cells that can undergo 50,000 voltage cycles with a negligible decay in their catalytic activity and no apparent changes in their structure or elemental composition.

In a paper published in Science, the team reports on a class of platinum-lead/platinum (PtPb/Pt) core/shell nanoplate catalysts that exhibit large biaxial strains. (Modifying the electronic structure of catalysts can improve their performance; lattice strain (either compressive or tensile) modifies the distances between surface atoms and hence modifies catalytic activity. Earlier post.) The stable Pt (110) facets of the nanoplates have high ORR specific and mass activities that reach 7.8 milliampere (mA) per cm2 and 4.3 ampere per milligram of platinum at 0.9 volts versus the reversible hydrogen electrode (RHE), respectively.

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Single Pt atom catalysts show enhanced catalytic activity for water-splitting; potential to drive down electrolysis cost

December 12, 2016

A research team from University of Western Ontario, McMaster University and Beijing Computational Science Research Center has developed an effective synthesis method to produce isolated single platinum (Pt) atoms and clusters for use as catalysts for the hydrogen evolution reaction (HER) in water splitting to produce hydrogen.

In an open-access paper published in Nature Communications, the researchers reported that the single Pt atom catalysts exhibit significantly enhanced catalytic activity (up to 37 times) and high stability in comparison to the state-of-the-art commercial platinum/carbon (Pt/C) catalysts.

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Stanford team uses battery electrode materials to boost platinum catalytic performance for fuel cells

November 25, 2016

A team at Stanford University has developed a method for using battery electrode materials directly and continuously to control the lattice strain of a platinum (Pt) catalyst, thereby boosting catalytic activity for the oxygen reduction reaction (ORR) in fuel cells by up to nearly 90%. A paper on their work is published in Science.

Modifying the electronic structure of catalysts can improve their performance; lattice strain (either compressive or tensile) modifies the distances between surface atoms and hence modifies catalytic activity. However, the common approach of using metal overlayers to induce strain has some control issues, such as introducing ligand effects.

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S. Korean researchers develop new catalytic pathway for direct conversion of CO2 to liquid hydrocarbon fuels

November 21, 2016

A team led by Professor Jae Sung Lee at Ulsan National Institute of Science and Technology (UNIST), with colleagues at Pohang University of Science and Technology (POSTECH), have developed a new pathway for the direct conversion of CO2 to liquid transportation fuels by reaction with renewable hydrogen produced by solar water splitting.

The new carbon capture and utilization (CCU) system is enabled by their discovery of a new catalyst that produces liquid hydrocarbon (C5+) selectivity of ∼65% and greatly suppresses CH4 formation to 2–3%. This selectivity is unprecedented for direct catalytic CO2 hydrogenation and is very similar to that of conventional CO-based Fischer-Tropsch (FT) synthesis, the team reports in a paper published in Applied Catalysis B: Environmental.

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Ultrafine jagged Pt nanowires extremely efficient ORR catalysts; 50x more power than current commercial catalyst

November 18, 2016

An international team led by researchers at UCLA and Caltech has demonstrated that altering the form of platinum nanoscale wires from a smooth surface to a jagged one can significantly reduce the amount of precious metal required as a catalyst for the oxygen reduction reaction (ORR) in fuel cells and thus lower the cost. According to the findings, the newly developed catalyst is so active that the amount of platinum required for a fuel cell could be 1/50 of what is needed today.

In a paper published in Science, the team reports that the jagged Pt nanowires exhibit an ECSA (electrochemical active surface area) of 118 m2 per gram Pt and a specific activity of 11.5 mA per square centimeter for ORR for a mass activity of 13.6 ampere per milligram Pt, nearly doubling previously reported best values. Reactive molecular dynamics simulations suggested that the highly stressed, under-coordinated rhombohedral-rich surface configurations of the jagged nanowire enhanced ORR activity versus more relaxed surfaces.

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Univ. Houston, Caltech team develops new earth-abundant, cost-effective catalyst for water-splitting

September 20, 2016

A team of researchers from the University of Houston and the California Institute of Technology has developed an active and durable earth-abundant transition metal dichalcogenide-based hybrid catalyst for water-splitting that exhibits high hydrogen evolution activity approaching the state-of-the-art platinum catalysts. The new catalyst also offers activity superior to that of most transition metal dichalcogenides (molybdenum sulfide, cobalt diselenide and so on).

The material is fabricated by growing ternary molybdenum sulfoselenide particles on self-standing porous nickel diselenide foam. In an open-access paper in the journal Nature Communications, the team said that their advance provides a different pathway to design cheap, efficient and sizable hydrogen-evolving electrode by simultaneously tuning the number of catalytic edge sites, porosity, heteroatom doping and electrical conductivity.

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SLAC, Stanford team develops new catalyst for water-splitting for renewable fuels production; 100x more efficient than other acid-stable catalysts

September 02, 2016

Researchers at Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory have developed a new highly active and stable IrOx/SrIrO3 catalyst for the oxygen evolution reaction (OER).

The new catalyst outperforms known IrOx and ruthenium oxide (RuOx) systems, the only other OER catalysts that have reasonable activity in acidic electrolyte. Because it requires less of the rare and costly metal iridium, the new catalyst could bring down the cost of artifical photosynthetic processes that use sunlight to split water molecules—a key step in a renewable, sustainable pathway to produce hydrogen or carbon-based fuels that can power a broad range of energy technologies. The team published their results in the journal Science.

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SLAC, Utrecht Univ. team visualize poisoning of FCC catalysts used in gasoline production; seeing changes in pore network materials

August 31, 2016

Merging two powerful 3-D X-ray techniques, a team of researchers from the Department of Energy’s SLAC National Accelerator Laboratory and Utrecht University in the Netherlands revealed new details of the metal poisoning process that clogs the pores of fluid catalytic cracking (FCC) catalyst particles used in gasoline production, causing them to lose effectiveness.

The team combined their data to produce a video that shows the chemistry of this aging process and takes the viewer on a virtual flight through the pores of a catalyst particle. More broadly, the approach is generally applicable and provides an unprecedented view of dynamic changes in a material’s pore space—an essential factor in the rational design of functional porous materials including those use for batteries and fuel cells. The results were published in an open access paper in Nature Communications.

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Dalian team synthesizes advanced catalytic layer for fuel cell MEAs; low Pt-loading, high mass activity

August 29, 2016

Researchers at Dalian Institute of Chemical Physics (China) have synthesized an advanced catalytic layer in the membrane electroide assembly (MEA) for proton exchange membrane fuel cells (PEMFCs) using vertically aligned polymer–polypyrrole (PPy) nanowire arrays as ordered catalyst supports.

In a paper published in the Journal of Power Sources, they report that a single cell fitted with their MEA yields a maximum performance of 762.1 mW cm−2 with a low Pt loading (0.241 mg Pt cm−2, anode + cathode). The advanced catalyst layer indicates better mass transfer in high current density than that of commercial Pt/C-based electrode. The mass activity is 1.08-fold greater than that of US Department of Energy (DOE) 2017 target.

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New approach for synthetic rubber for degradable tires: converting cyclopentene to polypentenamers

August 22, 2016

A team from the Texas A&M University campus in Qatar (TAMU-Qatar) and Caltech has developed a new way to make synthetic rubber; once this material is discarded, it can be easily degraded back to its chemical building blocks and reused in new tires and other products. The researchers will present their work today at the 252nd National Meeting & Exposition of the American Chemical Society (ACS) in Philadelphia.

According to the Rubber Manufacturers Association, nearly 270 million tires were discarded in the US in 2013—more than one tire per adult living in the country. Many of the non-degradable scrap tires get stockpiled in landfills. More than half go on to become tire-derived fuel—shredded scrap tires that get mixed with coal and other materials to help power cement kilns, pulp and paper mills and other plants. But environmentalists are concerned that the emissions from this practice could be adding harmful pollutants to the air.

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Vanderbilt, Nissan and Georgia Tech partner on new low PGM electrospun nanofiber catalysts for improved automotive fuel cells

August 09, 2016

Vanderbilt University, Nissan North America and Georgia Institute of Technology are collaborating to test a new technique to electospin low-platinum-metal-group (low PGM) electrocatalysts with a proton-conducting binder to improve durability and performance of fuel cell electrodes. The project is one of four awarded a combined $13 million by the Department of Energy program to advance fuel cell performance and durability and hydrogen storage technologies announced last month. (Earlier post.)

The $4.5-million collaboration is based on nanofiber mat technology developed by Peter Pintauro, the H. Eugene McBrayer Professor of Chemical Engineering at Vanderbilt, that replaces the conventional electrodes used in fuel cells. The nanofiber electrodes boost the power output of fuel cells by 30% while being less expensive and more durable than conventional catalyst layers.

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Argonne team discovers self-regenerating DLC tribofilm

August 05, 2016

Researchers at Argonne National Laboratory have discovered an ultra-durable, self-lubricating tribofilm that regenerates in the presence of oil, heat, and pressure—meaning that it will not wear away over the life of an engine. The film, reported yesterday in the journal Nature, develops when a new catalytic coating that can be applied to engine parts interacts with lubricating oil to create an extremely tough coating that almost eliminates wear.

Tests revealed the diamond-like carbon (DLC) tribofilm reduced friction by 25-40% and that wear was reduced to unmeasurable values. The discovery could have implications for the efficiency and durability of future engines and other moving metal parts that can be made to develop self-healing DLC tribofilms.

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UI, Argonne develop catalyst for more efficient solar-powered reduction of CO2 to CO for conversion to fuel

August 01, 2016

In a new study from the US Department of Energy’s Argonne National Laboratory and the University of Illinois at Chicago, researchers report devising a new transition metal dichalcogenide (TMDC) nanoarchitecture for catalytic electrochemical reduction of CO2 to carbon monoxide (CO) in an ionic liquid.

In their paper published in the journal Science, the researchers found that tungsten diselenide nanoflakes show a current density of 18.95 milliamperes per square centimeter, CO faradaic efficiency of 24%, and CO formation turnover frequency of 0.28 per second at a low overpotential of 54 millivolts. They also applied this catalyst in a light-harvesting artificial leaf platform that concurrently oxidized water in the absence of any external potential.

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Researchers identify pentlandite as equally efficient alternative to platinum for hydrogen production

July 27, 2016

Researchers have identified artificially-produced pentlandite (a natural ore, Fe4.5Ni4.5S8) as a direct ‘rock’ electrode without the need of further surface modifications for hydrogen evolution under acidic conditions. The pentlandite provides high activity and stability at low overpotential for H2 generation. According to their study, artificial pentlandite is just as efficient as the platinum electrodes commonly used today for the electrolytic production of hydrogen from water, but is lower cost.

A team headed by Dr. Ulf-Peter Apfel and Prof. Dr. Wolfgang Schuhmann of the Ruhr-Universität Bochum describes the results of their work together with colleagues from the Max-Planck-Institute for Coal Research in Mülheim an der Ruhr and the Technical University of Bratislava in an open-access paper published in Nature Communications.

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Rice team develops “antenna-reactor” plasmonic catalysts for increased energy savings and efficiency in catalytic processes

July 24, 2016

Researchers at Rice University’s Laboratory for Nanophotonics (LANP), with colleagues at Princeton University, have developed a new method for uniting light-capturing photonic nanomaterials and high-efficiency metal catalysts, creating an “antenna-reactor” plasmonic catalyst.

By placing a catalytic reactor particle adjacent to a plasmonic antenna, the highly efficient and tunable light-harvesting capacities of plasmonic nanoparticles can be exploited to increase absorption and hot-carrier generation significantly in the reactor nanoparticles. The modularity of this approach provides for independent control of chemical and light-harvesting properties and paves the way for the rational, predictive design of efficient plasmonic photocatalysts, the researchers suggest in their open-access paper, published in Proceedings of the National Academy of Sciences (PNAS).

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UK team produces hydrogen from fescue grass via photocatalytic reforming

July 21, 2016

A team of researchers from the UK’s Cardiff University’s Cardiff Catalysis Institute and Queen’s University Belfast have shown that significant amounts of hydrogen can be unlocked from fescue grass—without significant pre-treatment—using sunlight and a metal-loaded titania photocatalyst. An open access paper on their work is published in Proceedings of the Royal Society A.

Based on their study, the team proposed that the first step in their photoreforming of cellulose was the (photo)hydrolysis of cellulose into glucose, with the latter then undergoing reforming to hydrogen and CO2. It is the first time that this method has been demonstrated and could potentially lead to a sustainable way of producing hydrogen.

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Los Alamos team develops robust route to convert starch and sugar to C10 and C11 hydrocarbons; “potato-to-pump”

July 18, 2016

Researchers at Los Alamos National Laboratory have developed a route to convert oligosaccharides, such as starch, cellulose, and hemicelluloses to C10 and C11 hydrocarbons by using depolymerization followed by chain extension.

In a paper published in the journal ChemSusChem, they report on the robustness of the approach by performing a simple starch extraction from a Russet potato and subjecting it to their process. (They noted that the use of the potato was simply illustrative, and that the use of food crops for fuel production should be avoided.)

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Toyota Tsusho strategic equity investor in bio-BTX company Anellotech

July 11, 2016

Catalytic pyrolysis company Anellotech, which focuses on producing cost-competitive BTX (benzene, toluene and xylene) from non-food biomass, revealed Toyota Tsusho Corporation as a multinational strategic equity investor and corporate partner in the renewable aromatic chemicals supply chain. The renewable aromatic chemical can be used use in making plastics such as polyester, nylon, polycarbonate, polystyrene, or for renewable transportation fuels.

Toyota Tsusho is a member of the Toyota Group and is one of the major value chain partners (along with Suntory) in the Anellotech alliance, further validating the global market opportunity for Anellotech’s Bio-TCat technology.

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Researchers use ceria to trap platinum atoms, improving catalyst efficiency and enabling reduced loading

July 08, 2016

Researchers from the University of New Mexico, Washington State University, and GM Global R&D have developed a novel approach to trap platinum atoms used in catalysts, preventing their agglomeration and the resultant reduction of catalyst efficiency. By trapping the platinum to prevent agglomeration, the process enables the atoms to continue their activity, enabling lower loading and thus lower cost. A paper on the work is published in the journal Science.

Platinum is used as a catalyst in many clean energy systems, including in catalytic converters and fuel cells. The precious metal facilitates chemical reactions for many commonly used products and processes, such as converting poisonous carbon monoxide to less harmful carbon dioxide in catalytic converters. Because of platinum’s expense and scarcity, industries are continually looking to use less of it and to develop catalysts that more efficiently use individual platinum atoms in reactions. At high temperatures, however, the atoms become mobile and fly together into clumps, which reduces catalyst efficiency and performance. This is the primary reason catalytic converters are tested regularly for effectiveness.

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