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 Molecular switch detects metals in the environment
15.08.2018 | Université de Genève

nachricht Breakthrough in nanoresearch - Quantum chains in graphene nanoribbons
09.08.2018 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Unraveling the nature of 'whistlers' from space in the lab

15.08.2018 | Physics and Astronomy

Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide

15.08.2018 | Earth Sciences

Early opaque universe linked to galaxy scarcity

15.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>