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Researchers at the U.S. Department of Energy’s 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.
Their ultimate goal is to find ways to use solar energy — either directly or via electricity generated by solar cells — to convert the end products of hydrocarbon combustion, water and carbon dioxide, back into a carbon-based fuel. Dubbed “artificial photosynthesis,” this process mimics how plants convert those same ingredients to energy in the form of sugars. One key step is splitting water, or water electrolysis.

“By splitting liquid water (H2O) into hydrogen and oxygen, the hydrogen can be regenerated as a gas (H2) and used directly as fuel,” explains Etsuko Sasaki, member of the Broohaven team.
“A very promising route to making a carbon-containing fuel is to hydrogenate carbon dioxide (or carbon monoxide) using solar-produced hydrogen,” adds Fujita, who leads the artificial photosynthesis group in the Brookhaven Chemistry Department.

Source: http://www.bnl.gov/

A new method of harvesting the Sun’s energy is emerging, thanks to scientists at UC Santa Barbara‘s Departments of Chemistry, Chemical Engineering, and Materials. Though still in its infancy, the research promises to convert sunlight into energy using a process based on metals that are more robust than many of the semiconductors used in conventional methods.

“When nanostructures, such as nanorods, of certain metals are exposed to visible light, the conduction electrons of the metal can be caused to oscillate collectively, absorbing a great deal of the light,” said Martin Moskovits, professor of chemistry at UCSB.. “This excitation is called a surface plasmon.”
“It is the first radically new and potentially workable alternative to semiconductor-based solar conversion devices to be developed in the past 70 years or so,” said Moskovits.
Source: http://www.ia.ucsb.edu/

New technology could help power portable devices like satellite phones and radios. University at Buffalo researchers demonstrate that super-small particles of silicon react with water to produce hydrogen almost instantaneously. In a series of experiments, the scientists created spherical silicon particles about 10 nanometers in diameter. When combined with water, these particles reacted to form silicic acid (a nontoxic byproduct) and hydrogen — a potential source of energy for fuel cells. The reaction didn’t require any light, heat or electricity, and also created hydrogen about 150 times faster than similar reactions using silicon particles 100 nanometers wide, and 1,000 times faster than bulk silicon, according to the study.

“When it comes to splitting water to produce hydrogen, nanosized silicon may be better than more obvious choices that people have studied for a while, such as aluminum,” said researcher Mark T. Swihart, UB professor of chemical and biological engineering and director of the university’s Strategic Strength in Integrated Nanostructured Systems. The scientists were able to verify that the hydrogen they made was relatively pure by testing it successfully in a small fuel cell that powered a fan.
Source: http://www.buffalo.edu/

Nanometer-scale structures consisting of cheap metal and oxide spheres were recently demonstrated as an excellent catalyst for a hydrogen-production reaction powered only by sunlight. The study was completed by Ming-Yong Han and his colleagues of the A*STAR Institute of Materials Research and Engineering, Singapore, working in collaboration with a team of researchers from Singapore and France. Hydrogen is crucial for the oil-refining industry and the production of essential chemicals such as the ammonia used in fertilizers. It may be also the future of the electric car. Since producing hydrogen is costly, scientists have long searched for alternative, energy-efficient methods to separate hydrogen atoms from abundant sources such as water.

“Our work provides insight into mechanisms that will be useful for the future development of high-performance photocatalysts,” says Han. Indeed, Han and his co-workers were able to improve the efficiency of the hydrogen production even further: they increased the area of the metal-oxide interface by using larger gold nanoparticles.
The Janus particles were 100 times more efficient as a catalyst for hydrogen production than bare gold nanoparticles. Moreover, they were over one-and-a-half times better than another common type of plasmonic nanoparticle, core-shell particles, in which the oxide material forms a coating around the metal nanoparticle.
Source: http://www.research.a-star.edu.sg/research/6552

Researching for clean energy generation,  scientists at Harvard University have demonstrated  that  a solid-oxide fuel cell (SOFC) that converts hydrogen into electricity,  can also store electrochemical energy like a battery. This fuel cell can continue to produce power for a short time after its fuel has run out.

“Unmanned aerial vehicles, for instance, would really benefit from this,” says lead author Quentin Van Overmeere, a postdoctoral fellow at the Harvard School of Engineering and Applied Sciences (SEAS). “When it’s impossible to refuel in the field, an extra boost of stored energy could extend the device’s life span significantly.” The finding, which appeared online in the journal Nano Letters, will be most important for small-scale, portable energy applications, where a very compact and lightweight power supply is essential and the fuel supply may be interrupted.

Source: http://news.harvard.edu/gazette/story/2012/06/fuel-cell-keeps-going-after-hydrogen-runs-out/

Chemical reactions on the surface of metal oxides, such as titanium dioxide and zinc oxide, are important for applications such as solar cells that convert the sun's energy to electricity. Now University of Washington scientists have found that a previously unappreciated aspect of those reactions could be key in developing more efficient energy systems.

New systems could include cells that would produce more electricity from the sun's rays, or hydrogen fuel cells efficient enough for use in automobiles, said James Mayer, a UW chemistry professor. "As we think about building a better energy future, we have to develop more efficient ways to convert chemical energy into electrical energy and vice versa," said Mayer.

Chemical reactions that change the oxidation state of molecules on the surface of metal oxides historically have been seen as a transfer solely of electrons. The new research shows that, at least in some reactions, the transfer process includes coupled electrons and protons.
Source: http://www.newswise.com/articles/new-twist-on-old-chemical-process-could-boost-energy-efficiency

Hydrogenation and hydrogenolysis reactions have huge applications in many key industrial sectors, including the petrochemical, pharmaceutical, food and agricultural industries. "In the petrochemical industry, for example, upgrading of oil to gasoline, and in making various biomass-derived products, you need to hydrogenate molecules — to add hydrogen – and all this happens through catalytic transformations," says Professor Manos  Mavrikakis. from the University of Wisconsin-Madison.

Through an interaction with hydrogen atoms (green), a water molecule (magenta and blue) moves rapidly across a metal oxide surface. This atomic-scale speed leads to more efficient chemical reactions. 

In a recent research, Mavrikakis and Professor Besenbacher from the University of Aarhus, Denmark drew on their respective theoretical and experimental expertise to study metal oxides, a class of materials often used as catalysts or catalyst supports. They found that the presence of even the most minute amounts of water — on the order of those in an outer-space vacuum — can accelerate the diffusion of hydrogen atoms on iron oxide by 16 orders of magnitude at room temperature. In other words, water makes hydrogen diffuse 10,000 trillion times faster on metal oxides than it would have diffused in the absence of water. Without water, heat is needed to speed up that motion.

Source: http://www.news.wisc.edu/20697
Led by Manos Mavrikakis, the Paul A. Elfers professor of chemical and biological engineering at the University of Wisconsin-Madison, and Flemming Besenbacher, a professor of physics and astronomy at the University of Aarhus, Denmark, the team published its findings in the May 18 issue of the journal Science.