Category Chemistry/Nanotechnology

Zeolitic ice ITT (left) and aeroice 4xFAU (right) are illustrated. Their structure can be regarded as combinations of a couple of polyhedral building blocks. In molecular scale, each polygonal face of the polyhedra is made of water molecules (left bottom). Yellow lines are hydrogen bonds. Credit: Masakazu Matsumoto/CC BY 2.0

Researchers from Japan have discovered a new form of ice crystal from theoretical modeling of its formation under negative pressure. Not much is known about the effects of extreme negative pressure on water molecules. Exploring a significant region of negative pressure through molecular dynamic simulations, researchers have now theoretically discovered a new family of ice phases. Called aeroices, these ices have the lowest density of all known ice crystals.

“Our resear...

Schematic of a two-step method for the synthesis of transition metal carbide nanoparticles dispersed on a carbon material

Researchers have developed a new technology that could speed up the commercialization of fuel cell vehicles. A team of engineers at the University of Delaware has made a catalyst of tungsten carbide, which goes for around $150/kg instead of using expensive platinum at $30,000/kg. They produced tungsten carbide nanoparticles in a novel way, much smaller and more scalable than previous methods.

“The material is typically made at very high temperatures, about 1,500 Celsius, and at these temperatures, it grows big and has little surface area for chemistry to take place on,” said Dionisios Vlachos, director of UD’s Catalysis Center for Energy Innovation...

The weak electron-donating capability of ruthenium (Ru) nanoparticles supported on niobium pentoxide (Nb2O5) is thought to promote reductive amination while preventing the formation of undesirable by-products. Credit: JACS

Researchers have developed a highly efficient reusable catalyst for the production of primary amines. By cutting the amount of undesired by-products, the catalyst is set to revolutionize the production of bio-based fuels, pharmaceuticals, agricultural chemicals and more. Primary amines (derivatives of ammonia) are industrially important compounds used in the preparation of a wide range of dyes, detergents and medicines...

Phase-Defined van der Waals Schottky Junctions with Significantly Enhanced Thermoelectric Properties. The Journal of Physical Chemistry Letters, 2017; 8 (13): 2887 DOI: 10.1021/acs.jpclett.7b01089

A new device being developed by Washington State University physicist Yi Gu could one day turn the heat generated by a wide array of electronics into a usable fuel source. The device is a multicomponent, multilayered composite material called a van der Waals Schottky diode. It converts heat into electricity up to 3X more efficiently than silicon – a semiconductor material widely used in the electronics industry. While still in an early stage of development, the new diode could eventually provide an extra source of power for everything from smartphones to automobiles.

“The ability of our diode to ...