Category Chemistry/Nanotechnology

This is an image of the change in luminescence colors of MCL materials. Credit: Youhei Takeda

Mechanochromic luminescent (MCL) materials change their color in response to a change in their environment, like pressure and temperature. To date, most MCL materials only change between 2 colors, limiting their applications. The international research team comprising of chemists at Osaka University and physicists at Durham University has developed tricolor-changing MLC materials. Not only that, the developed materials exhibited efficient thermally activated delayed fluorescence (TADF) and allowed high performance organic light-emitting diodes (OLEDs) devices.

“Most MCL materials generate 2 colors by switching between a stable state and one metastable state...

Photoluminescent compounds synthesized by the Coordination Chemistry and Catalysis Unit glowing under a UV light. Credit: Image courtesy of Okinawa Institute of Science and Technology Graduate University – OIST

Chemical compounds that emit light are used in a variety of different materials, from glow-in-the-dark children’s toys to LED lights to light-emitting sensors. As the demand for these compounds increases, finding new efficient methods for their production is essential. New research describes a new strategy for producing photoluminescent (PL) compounds with increased capabilities.

Production of PL compounds is typically centered around 2 main methods: the conventional metal-ligand system or an aggregation based system...

Hydrogenation forms a mixture of lithium amide and hydride (light blue) as an outer shell around a lithium nitride particle (dark blue) nanoconfined in carbon. Nanoconfinement suppresses all other intermediate phases to prevent interface formation, which has the effect of dramatically improving the hydrogen storage performance

Lawrence Livermore scientists have collaborated with an interdisciplinary team of researchers including colleagues from Sandia National Laboratories to develop an efficient hydrogen storage system that could be a boon for hydrogen powered vehicles. Hydrogen is an excellent energy carrier, but the development of lightweight solid-state materials for compact, low-pressure storage is a huge challenge.

Complex metal hydrides are a promising class of hydrogen storage mate...

Geoffrey Coates, center, in his lab with James Eagan, a postdoctoral researcher in Coates’ group and researcher Anne LaPointe. Credit: Robert Barker/University Photography

When Geoffrey Coates, Tisch University Professor of Chemistry and Chemical Biology, gives a talk about plastics and recycling, he usually opens with this question: What percentage of the 78 million tons of plastic used annually for packaging – for example, a 2-liter bottle or a take-out food container – actually gets recycled and reused in a similar way? The answer is just 2%. Sadly, nearly a third is leaked into the environment, around 14% is used in incineration and/or energy recovery, and a whopping 40% winds up in landfills.

One of the problems: Polyethylene (PE) and polypropylene (PP), 2/3 of the world’s plastic...