Inorganic chalcogenide (WS2) nanotubes have shown revolutionary chemical and physical properties that offer a broad range of applications. They are ultra-strong impact-resistant materials.
This makes them excellent candidates for producing bullet proof vests, helmets, car bumpers, high strength glues and binders, and other safety equipment. The unique nanotubes are up to four to five times stronger than steel and about six times stronger than Kevlar, the nowadays most popular material used for bullet proof vests.
In addition to ballistic protection materials and polymer composites, WS2 nanotubes can be implemented in nanoelectronics, fuel cells, ultra-filtration membranes, and catalysts. Their optical properties allow various other applications in fields such as nanolithography or photocatalysis.
Up to now a major obstacle in the application of chalcogenide nanotubes has been their inherently inertness to chemical and biological modification and functionalization. Their potential use in composite materials might be greatly enhanced by improving the chalcogenide/matrix interface bonding. Scientists at Johannes Gutenberg University Mainz (JGU) devised a novel modification strategy based on metal oxide nanoparticles as universal vehicles for a reversible functionalization of WS2 nanotubes. The groundbreaking research conducted in the group of Wolfgang Tremel, Professor in the Department of Chemistry at JGU, and Dr. Ute Kolb at the Electron Microscopy Center was published in advance online on August 16 and will appear on the cover of the journal Angewandte Chemie.
The strategy underlying the reversible binding between chalcogenide nanotubes and metal oxide nanoparticles is based on "Pearson hardness," an elementary concept introduced more than 40 years ago to classify the Lewis acids and bases (especially the various commonly used metal ions and ligands) into three broad categories - hard, soft, and borderline. Metal oxides nanoparticles stick to the surface of chalcogenide nanotubes. As these metal oxide particles can carry many other functional molecules (e.g. polymers, biomolecules) as well, they can act as interfacial glue between the nanotubes and organic matter. This interfacial glue, however, can be detached purposely by the addition of substances that exhibit a stronger binding to the oxide nanoparticles than the WS2 nanotubes.
Hitherto all strategies of bonding to carbon or chalcogenide nanotubes were irreversible, i.e. once molecules have been bound they cannot be released again. The new, fully reversible attachment/detachment process will be applied in "smart materials" the toughness of which is reduced upon the influence of an external trigger. The findings will also provide a better understanding of fundamental friction issues, and - from a more practical point of view - offer a new tool for assembling nanotubes into devices and study the forces acting on them.
Strange but true: Turning a material upside down can sometimes make it softer
20.10.2017 | Universitat Autonoma de Barcelona
Metallic nanoparticles will help to determine the percentage of volatile compounds
20.10.2017 | Lomonosov Moscow State University
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research