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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.]

Tulane, SACHEM collaborate on SSZ-39 zeolite for improved SCR systems

September 21, 2017

Members of Tulane University’s Shantz Lab will collaborate with scientists from chemical science company SACHEM to develop next-generation materials to reduce automotive emissions. SACHEM is funding the effort.

Under the direction of Daniel Shantz, a professor of chemical and biomolecular engineering and the Entergy Chair of Clean Energy Engineering, the lab members and SACHEM scientists will collaborate to improve the performance of the zeolite SSZ-39 in the selective catalytic reduction of NOx in automotive exhaust.

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U. Houston-led project looking for new exhaust treatment catalysts for low-temperature lean-burn combustion engines

A chemical engineer from the University of Houston is leading a $2.1-million project to find new catalytic materials that work at lower exhaust temperatures, allowing automakers to build vehicles that operate more efficiently while retaining the ability to clean emissions before they leave the tailpipe.

Michael Harold, chairman of the Department of Chemical and Biomolecular Engineering at UH, will serve as principal investigator on the grant, funded by the US Department of Energy National Energy Technology Laboratory (DOE NETL). The project also includes researchers from the University of Virginia (UVA); Oak Ridge National Laboratory (ORNL); and Southwest Research Institute (SwRI). Engineers from Fiat-Chrysler Automobiles Inc. and Johnson Matthey Inc. also will be involved in the project.

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Berkeley Lab copper catalyst yields high-efficiency CO2-to-fuels conversion

September 19, 2017

Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a new electrocatalyst that can directly convert carbon dioxide into multicarbon fuels and alcohols using record-low inputs of energy. The work is the latest in a round of studies coming out of Berkeley Lab tackling the challenge of creating a clean chemical manufacturing system that can put carbon dioxide to good use.

In the new study, being published this week in the Proceedings of the National Academy of Sciences, a team led by Berkeley Lab scientist Peidong Yang discovered that an electrocatalyst made up of copper nanoparticles provided the conditions necessary to break down carbon dioxide to form ethylene, ethanol, and propanol.

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Ballard, Nisshinbo collaborate to offer first PEM fuel cell using non-precious-metal catalyst

September 13, 2017

Ballard Power Systems has collaborated with Nisshinbo Holdings to develop a Non-Precious-Metal Catalyst (NPMC) for use in the world’s first commercialized NPMC-based proton exchange membrane (PEM) fuel cell product. Nisshinbo and Ballard have jointly collaborated on the development of NPMC since 2013. (Earlier post.)

Ballard has successfully incorporated the Non Precious Metal Catalyst into a high performing catalyst layer under a Technology Solutions program and plans to launch a new 30-watt FCgen-1040 fuel cell stack product incorporating NPMC for commercial use in late-2017.

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Tokyo Tech: reusable ruthenium-based catalyst could advance large-scale production of biomass-derived materials

September 04, 2017

Researchers at the Tokyo Institute of Technology have developed a highly selective catalyst consisting of ruthenium nanoparticles supported on niobium pentoxide (Ru/Nb2O5). In a study published in the Journal of the American Chemical Society, the team demonstrated that Ru/Nb2O5 is capable of producing primary amines from carbonyl compounds with ammonia (NH3) and dihydrogen (H2), with negligible formation of by-products.

By pushing the boundaries of material design, the researchers say that Ru/Nb2O5 may accelerate the production of environmentally friendly plastics, rubber and heat-resistant aramid fibers. In future, the Ru/Nb2O5 catalyst may also impact the development of novel anti-cancer drugs, anti-bacterials, pesticides, agrochemicals, fertilizers, bio-oils and biofuels.

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Metallic nanostructures with strong light confinement can triple the efficiency of solar-based hydrogen generation

August 29, 2017

Researchers led by a team from KAUST have found a more sustainable route to hydrogen fuel production using chaotic, light-trapping materials that mimic natural photosynthetic water splitting. In a paper in the journal Advanced Materials, the researchers report a new photocatalyst for hydrogen evolution based on metal epsilon-near-zero (ENZ) metamaterials.

The authors designed these to achieve broadband strong light confinement at the metal interface across the entire solar spectrum. Using electron energy loss spectroscopy, the authors show that hot carriers are generated in a broadband fashion within 10 nm in this system. The resulting photocatalyst achieves a hydrogen production rate of 9.5 µmol h−1 cm−2 that exceeds, by a factor of 3.2, that of the best previously reported plasmonic-based photocatalysts for the dissociation of H2 with 50 h stable operation.

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Researchers develop cheaper, greener biofuels processing catalyst using waste metals and bacteria

August 25, 2017

A team from the Prairie Research Institute at the University of Illinois, with colleagues from the University of Birmingham and Aarhus University, have developed a nanosized bio-Pd/C catalyst for upgrading algal bio-oil.

Published in an open-access paper in the journal Fuel, their findings point to a cheaper, more environmentally friendly and renewable catalyst for processing that uses common bacteria and the metal palladium, which can be recovered from waste sources such as discarded electronics, catalytic converters, street sweeper dust and processed sewage.

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Purdue, Notre Dame, Cummins discovery could lead to new SCR catalyst design for improved NOx control

August 18, 2017

Researchers at Purdue University, the University of Notre Dame and Cummins have discovered a new reaction mechanism that could be used to improve SCR catalyst designs for pollution-control systems to further reduce emissions of smog-causing nitrogen oxides in diesel exhaust. The research focuses on zeolites—workhorses in petroleum and chemical refineries and in emission-control systems for diesel engines.

The key challenge in reducing emissions is that they can occur over a very broad range of operating conditions, and especially exhaust temperatures,” explained Rajamani Gounder, the Larry and Virginia Faith Assistant Professor of Chemical Engineering in Purdue University’s Davidson School of Chemical Engineering. “Perhaps the biggest challenge is related to reducing NOx at low exhaust temperatures, for example during cold start or in congested urban driving.” Current NOx reduction technologies only work well at relatively high temperatures.

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U Delaware team develops efficient catalyst for production of renewable jet-fuel-range alkanes from biomass under mild conditions

August 16, 2017

A team at the University of Delaware has synthesized renewable jet-fuel-range alkanes by hydrodeoxygenation of lignocellulose-derived high-carbon furylmethanes over ReOx-modified Ir/SiO2 catalysts under mild reaction conditions (170 ˚C, 5 MPa). Their paper is featured on the cover of the journal ChemSusChem.

In their work, they found that Ir−ReOx/SiO2 with a Re/Ir molar ratio of 2:1 exhibits the best performance, achieving a combined alkanes yield of 82–99% from C12–C15 furylmethanes. The catalyst can be regenerated in three consecutive cycles with only about 12% loss in the combined alkanes yield.

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ORNL, LANL study provides insights into performance of non-precious metal fuel-cell catalysts; atomic-level observations

August 04, 2017

In order to reduce the cost of next-generation polymer electrolyte fuel cells for vehicles, researchers have been developing alternatives to the prohibitively expensive platinum and platinum-group metal (PGM) catalysts currently used in fuel cell electrodes. New work at Los Alamos (LANL) and Oak Ridge national laboratories (ORNL) is now resolving difficult fuel-cell performance questions, both in determining efficient new materials and understanding how they work at an atomic level. The research is described this week in the journal Science.

Building on previous studies, the Los Alamos-led team has synthesized catalysts comprising low-cost platinum alternatives—iron-nitrogen-carbon catalysts synthesized with two nitrogen precursors that developed hierarchical porosity—that yield performance comparable to the standard PGM fuel cell catalyst used in vehicle applications. Current densities recorded in the kinetic region of cathode operation, at fuel cell voltages greater than ~0.75 V, were the same as those obtained with a Pt cathode at a loading of 0.1 milligram of Pt per centimeter squared.

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Rice University lab develops dual-surface graphene electrode to split water into hydrogen and oxygen

Researchers in the Rice University lab of chemist James Tour have produced dual-surface laser-induced graphene (LIG) electrodes on opposing faces of a plastic sheet that split water into hydrogen on one side and oxygen on the other side. The high porosity and electrical conductivity of LIG facilitates the efficient contact and charge transfer with the requisite electrolyte. A paper on the work is published in the journal ACS Applied Materials and Interfaces.

The LIG-based electrodes exhibit high performance for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with excellent long-term stability. The overpotential reaches 100 mA/cm2 for HER and OER is as low as 214 and 380 mV with relatively low Tafel slopes of 54 and 49 mV/dec, respectively. (One decade (symbol dec) is a factor of 10 difference between two numbers measured on a log scale.)

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Rice, Lawrence Livermore scientists develop new efficient non-Pt MX2 catalyst for efficient hydrogen production; Materials Genome Initiative in action

August 01, 2017

Scientists at Rice University and the Lawrence Livermore National Laboratory have predicted and created new two-dimensional electrocatalysts—low-cost, layered transition-metal dichalcogenides (MX2) based on molybdenum and tungsten—to extract hydrogen from water with high performance and low cost. In the process, they also created a simple model to screen materials for catalytic activity.

In a paper in Nature Energy, the report that the materials, beyond demonstrating high catalytic activity, exhibit an unusual ability to optimize their morphology for enhanced charge transfer and accessibility of active sites as the hydrogen evolution reaction (HER) proceeds, thereby offering a practical advantage for scalable processing. The catalysts reach 10 mA cm−2 current density at an overpotential of ∼50–60mV with a loading of 10–55 μg cm−2,surpassing other reported MX2 candidates without any performance-enhancing additives.

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Photo-activated catalyst converts CO2 to CO for clean fuel technology; no unwanted byproducts

July 31, 2017

An international research team led by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Nanyang Technological University (NTU) in Singapore have developed a light-activated material that can chemically convert carbon dioxide into carbon monoxide without generating unwanted byproducts.

When exposed to visible light, the material, a “spongy” nickel organic crystalline structure, converted the CO2 in a reaction chamber exclusively into carbon monoxide (CO) gas, which can be further turned into liquid fuels, solvents, and other useful products. An open-access paper on the work is published in the journal Science Advances.

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Japan team reports pathway to green ammonia: photocatalytic conversion of nitrogen with water

July 30, 2017

Researchers in Japan report that a commercially available TiO2 with a large number of surface oxygen vacancies, when photo-irradiated by UV light in pure water with nitrogen—successfully produces ammonia (NH3). The solar-to-chemical energy conversion efficiency is 0.02%, which is the highest efficiency among the early reported photocatalytic systems. This is, however, lower than that of natural photosynthesis (0.1%) and artificial photosynthesis such as overall water splitting and H2O2 production (0.2%).

Although improved catalytic activity is necessary, the noble-metal-free TiO2 system therefore shows a potential as a new artificial photosynthesis for green NH3 production, the team suggests in a paper published in the Journal of the American Chemical Society.

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New robust triple-layer bifunctional catalyst for water splitting with earth-abundant materials

July 27, 2017

A new robust and highly active bifunctional catalyst developed by Rice University and the University of Houston splits water into hydrogen and oxygen without the need for expensive metals such as platinum. The work, the team suggests, provides a facile strategy for fabricating highly efficient electrocatalysts from earth-abundant materials for overall water splitting.

The electrolytic film produced at Rice and tested at Houston is a three-layer structure of nickel, graphene and a ternary metal phosphide (FeMnP, iron, manganese and phosphorus). The foamy nickel gives the film a large surface, the conductive graphene protects the nickel from degrading and the metal phosphide carries out the reaction. A paper on the work is published in the journal Nano Energy.

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QUB team converts aluminum foil waste to highly active alumina; biofuel catalyst, other applications

Researchers at Queen’s University Belfast have developed a novel green route to convert aluminium foil waste into highly active nano-mesoporous alumina (γ-Al2O3) (designated as ACFL550). The material shows higher surface area, larger pore volume, and stronger acidity compared to γ-Al2O3 that is produced from the commercial AlCl3 precursor, AC550. An open access paper on the work appears in Nature’s Scientific Reports.

Aluminum oxide, alumina (Al2O3), is one of the most attractive ceramic materials for its various applications due to its thermal, chemical and mechanical stability. Alumina has direct application as a catalyst and catalyst support in the automotive and petroleum industries. The oxide offers a favorable combination of textural properties—such as surface area, pore volume, and pore-size distribution—and its acid/base characteristics, which are mainly related to surface chemical composition, local microstructure, and phase composition (Trueba and Trasatti, 2005).

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German team clarifies key catalytic step in enzymatic production of hydrogen

July 25, 2017

Enzymes, called [FeFe]-hydrogenases, efficiently turn electrons and protons into hydrogen; they are thus a candidate for the biotechnological production of the potential energy source. For years, researchers had assumed that a highly unstable intermediate state had to exist in the reaction. No one was able to verify this. Until now.

Now, researchers at Ruhr-Universität Bochum and the Freie Universität Berlin have clarified the crucial catalytic step in the production of hydrogen by enzymes. Led by Prof. Thomas Happe and Dr. Martin Winkler from the Bochum-based Photobiotechnology Working Group, with Berlin-based colleagues led by Dr. Sven Stripp, the team reports on the results in an open-access paper in the journal Nature Communications.

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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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