Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mainz University opens new vista in smart materials: Fully reversible functionalization of inorganic nanotubes

18.08.2010
Scientists at Johannes Gutenberg University Mainz (JGU), Germany have devised a tool which allows fully reversible binding of metal oxides to inorganic nanotubes

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.

Publication:
Jugal K. Sahoo, Muhammad N. Tahir, Aswani Yella, Thomas D. Schladt, Enrico Mugnaoli, Ute Kolb, Wolfgang Tremel: Reversible Self-Assembly of Metal Chalcogenide/Metal Oxide Nanostructures Based on Pearson Hardness
Angewandte Chemie, published online on August 16, 2010,
doi:10.1002/anie.20100774

Petra Giegerich | idw
Further information:
http://www.uni-mainz.de/eng/13759.php
http://dx.doi.org/10.1002/anie.201000774

More articles from Materials Sciences:

nachricht Switched-on DNA
20.02.2017 | Arizona State University

nachricht Using a simple, scalable method, a material that can be used as a sensor is developed
15.02.2017 | University of the Basque Country

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>