Category Chemistry/Nanotechnology

Konstantinos Giapis has shown how molecular oxygen may be produced on the surface of comets using lab experiments. He and his postdoctoral scholar Yunxi Yao fired high-speed water molecules (left) at oxidized silicon and iron surfaces, observing the production of a plume that included molecular oxygen. Oxygen atoms are red, and hydrogen, blue. Giapis says similar conditions exist on the comet 67P/Churyumov–Gerasimenko, where the European Space Agency’s Rosetta mission detected molecular oxygen.
Credit: Caltech

A Caltech chemical engineer has figured out how to explain a nagging mystery in space – why comets expel oxygen gas. The discovery that comets produce O2 – was announced in 2015 by researchers studying the comet 67P/Churyumov-Gerasimenko with the Rosetta spacecraft...

A team of researchers, led by the University of Minnesota, have discovered a new nano-scale thin film material with the highest-ever conductivity in its class.

A new nano-scale thin film material with the highest-ever conductivity in its class has been found by a team of researchers, led by the University of Minnesota. The new material could lead to smaller, faster, and more powerful electronics, as well as more efficient solar cells. Besides high conductivity, it also has a wide bandgap, which means light can easily pass through the material making it optically transparent. In most cases, materials with wide bandgap, usually have either low conductivity or poor transparency.

“The high conductivity and wide bandgap make this an ideal material for making optically transparent conducting fil...

Schematic of the pathway describing the evolution of adsorbed ethene (top left) to graphene (bottom left). The sequence of intermediates identified in the study and their respective appearance temperatures are indicated. Credit: F. Esch, R. Schaub, U. Landman

An international has developed a new way to produce single-layer graphene from a simple precursor: ethene aka ethylene – the smallest alkene molecule, which contains just two atoms of carbon. By heating the ethene in stages to a temperature of slightly >700C – hotter than had been attempted before – the researchers produced pure layers of graphene on a rhodium catalyst substrate. The stepwise heating and higher temperature overcame challenges in earlier efforts to produce graphene directly from hydrocarbon precursors.

Because of its l...

Scientists have developed a new molybdenum-coated catalyst that prevents an unwanted back reaction in certain chemical systems that split water into hydrogen and oxygen. (Andy Freeberg/SLAC National Accelerator Laboratory)

Hydrogen is one of the most promising clean fuels for use in cars, houses and portable generators. But water-splitting systems require a very efficient catalyst. Now an international research team, including scientists at DOE SLAC National Accelerator Laboratory, has developed a new catalyst with a molybdenum coating that prevents this problematic back reaction and works well in realistic operating conditions...