Fixation processes free up nitrogen atoms from their diatomic form, but nitrogen does not easily react with other chemicals to form new compounds. Researchers in South Korea have invented a simple and eco-friendly method of creating nitrogen-doped graphene nanoplatelets that simultaneously facilitates the nitrogen-fixation process and creates useful tools for building dye-sensitized solar cells and fuel cells.
Catalysts are everywhere. They make chemical reactions that normally occur at extremely high temperatures and pressures possible within factories, cars and the comparatively balmy conditions within the human body. Developing better catalysts, however, is mainly a hit-or-miss process. Now, researchers have shown a way to precisely design the active elements of a certain class of catalysts.
Catalysts are everywhere, but developing better catalysts is mainly a hit-or-miss process. Now, a study by researchers at the University of Pennsylvania, the University of Trieste, Italy, and Brookhaven National Laboratory has shown a way to precisely design the active elements of a certain class of catalysts, showing which parameters are most critical for improving performance.
The Air Force Office of Scientific Research has been working with Jim Tour’s laboratory at Rice University to make graphene suitable for a variety of organic chemistry applications. Recently, the partnership made another technological advance. Their work has shown that graphene nanoribbons can significantly increase the storage capacity of lithium ion by combining these 2D ribbons with tin oxide.
The research team from the Ulsan National Institute of Science and Technology in South Korea has developed an inexpensive and scalable bio-inspired composite electrocatalyst, designed using iron phthalocyanine, a macrocyclic compound, anchored to single-walled carbon nanotubes. Under certain conditions, the new catalyst has a higher electrocatalytic activity than platinum-based catalysts, and better durability during cycling.
There are a lot of small molecules people would like to convert to something useful. The current process for reducing nitrogen to ammonia is done under extreme conditions, and there is an enormous barrier to overcome to get a final product. Breaching that barrier more efficiently and reducing the huge amounts of energy used to convert nitrogen to ammonia has been a grail for the agricultural chemical industry, until now.
Hydrogenation is a chemical process used in a wide range of industrial applications, from food products to petrochemicals and pharmaceuticals. The process typically involves the use of heavy metals, such as palladium or platinum, which, though efficient, are expensive and can be toxic. However, researchers have discovered way to use iron as a catalyst for hydrogenation.
Waste from textile and paint industries often contains organic dyes such as methylene blue as pollutants. Photocatalysis is an efficient means of reducing such pollution, and molybdenum trioxide catalyzes this degradation. Researchers in India now report four methods to produce nanosheets made of very few layers of molybdenum trioxide, which are more efficient than their bulk counterparts.
Electrolysis is often used to produce hydrogen that can be used for a storable fuel. Modified solar cells with highly efficient architecture can use this method to obtain hydrogen from water with the help of catalysts. But these solar cells rapidly corrode in aqueous electrolytes. By embedding the catalysts in an electrically conducting polymer, researchers have prevented this corrosion while maintaining competitive efficiency.
Nanoscopic crystals of silicon assembled like skyscrapers on wafer-scale substrates are being intensely studied as a possible breakthrough in highly efficient battery technologies. A researcher at Northeastern University has been using computational to understand the atomic-scale interactions between the growth of nanowires and new development in this area of technology: alloyed metal droplets.
The research team of Ulsan National Institute of Science and Technology paved a new way to affordable fuel cells with efficient metal-free electrocatalysts using edge-halogenated graphene nanoplatelets. The research team, for the first time, reportedly synthesized a series of edge-selectively halogenated graphene nanoplatelets by ball-milling graphite flake in the presence of chlorine, bromine or iodine, respectively.
Catalysts can stop working when atoms on the surface of those materials start moving. At the Vienna University of Technology, this “dance” of the atoms has been observed and explained: A certain type of molecule initiates a clustering process, which causes the catalyst atoms, like palladium, to ball together and disappear from contact with the surrounding gas.
Silicon can accept ten times more lithium than the graphite used in the electrodes in lithium-ion batteries, but silicon also expands, shortening electrode life. Looking for an alternative to pure silicon, scientists in Germany have now synthesized a novel framework structure consisting of boron and silicon, which could serve as electrode material.
Los Alamos National Laboratory scientists have designed a new type of nanostructured-carbon-based catalyst that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells, providing for practical use of wind- and solar-powered electricity, as well as enhanced hybrid electric vehicles.
Chemical engineering researchers Wei Fan, Paul Dauenhauer, and colleagues at the University of Massachusetts Amherst report that they’ve discovered a new chemical process to make p-xylene, an important ingredient of common plastics, at 90% yield from lignocellulosic biomass, the highest yield achieved to date.
Ripening fruit, vegetables, and flowers release ethylene, which works as a plant hormone. Ethylene accelerates ripening, so other unripened fruit also begins to ripen—fruit and vegetables quickly spoil and flowers wilt. researchers in Japan have now introduced a new catalytic system for the fast and complete degradation of ethylene. This could keep the air in warehouses ethylene-free, keeping perishable products fresh longer.
A team from Argonne National Laboratory has worked for years to develop a new type of solar cell known as organic photovoltaics (OPVs). Because of their potential to reduce costs for both fabrication and materials, OPVs could be much cheaper to manufacture than conventional solar cells and have a smaller environmental impact as well. However, they aren’t as efficient as conventional solar cells due to one limitation.
Methanol to formaldehyde: This reaction is the starting point for the synthesis of many everyday plastics. Using catalysts made of gold particles, however, formaldehyde could be produced without the environmentally hazardous waste generated in conventional methods. But just how a gold catalyst could work has only recently been discovered by researchers.
Researchers from the U.S. Department of Energy’s (DOE) SLAC National Accelerator Laboratory and Stanford University have designed a low-cost, long-life battery that could enable solar and wind energy to become major suppliers to the electrical grid. The developers believe their new membrane-free battery, based on lithium and sulfur, may be the best yet designed to regulate alternative energies.
In recently published online paper, researchers at Brookhaven National Laboratory describe details of a low-cost, stable, effective catalyst that could replace costly platinum in the production of hydrogen. The catalyst, made from renewable soybeans and abundant molybdenum metal, produces hydrogen in an environmentally friendly, cost-effective manner, potentially increasing the use of this clean energy source.
A unique atomic-scale engineering technique for turning low-efficiency photocatalytic “white” nanoparticles of titanium dioxide into high-efficiency “black” nanoparticles could be the key to clean energy technologies based on hydrogen. Samuel Mao leads the development of a technique for engineering disorder into the nanocrystalline structure of the semiconductor titanium dioxide.
Controlling the shapes of nanometer-sized catalytic and electrocatalytic particles made from noble metals such as platinum and palladium may be more complicated than previously thought. Using systematic experiments, researchers have investigated how surface diffusion—a process in which atoms move from one site to another on nanoscale surfaces—affects the final shape of the particles.
Another innovative feature has been added to the world’s first practical “artificial leaf,” making the device even more suitable for providing people in developing countries and remote areas with electricity, scientists reported at the American Chemical Society’s National Meeting & Exposition this week. It gives the leaf the ability to self-heal damage that occurs during production of energy.
Researchers in Switzerland have used X-ray tomography to screen lithium-ion battery electrodes and have reconstructed these microstructures in high resolution. The flow behavior of the lithium ions, they have found, can be described by what is known as tortuosity. To put it simply, the more twisted the path of the ions through the electrode, the more slowly the battery is charged or discharged.
Wouldn't it be convenient if you could reverse the rusting of your car by shining a bright light on it? It turns out that this concept works for undoing oxidation on copper nanoparticles, and it could lead to an environmentally friendly production process for an important industrial chemical, University of Michigan engineers have discovered.