Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists track remarkable “breathing” in nanoporous materials

03.04.2007
Scientists all over the world are participating in the quest of new materials with properties suitable for the environmentally friendly and economically feasible separation, recovery, and reuse of vapours and greenhouse gases.

A team of scientists from France, UK and the ESRF have recently discovered an unprecedented giant and reversible swelling of nanoporous materials with exceptional properties: huge flexibility and profound selectivity. They publish their results in Science this week.

Porous hybrid solids are the new materials that could make the world more environmentally friendly. The team from Institut Lavoisier at University of Versailles have developed metal-organic three-dimensional structures with cages and channels (known as MIL, for Material Institut Lavoisier). These compounds contain metal ions (in this case chromium and iron), with organic linkers and are very flexible, and hence, can change shape very easily. They can open up or close down to external factors such as pressure, temperature, light or influence of gases and solvents.

The French researchers, in collaboration with the staff of the Swiss-Norwegian experimental station (called beamline) at the ESRF, have tracked, for the first time, a reversible giant increase in volume of these solids. It ranges from 85% of their size to up the unprecedented 230%. Such a large expansion in crystalline materials has not been observed before. This reversible “breathing” action is similar to the lungs’ function in humans: they grow in size when inhaling and go back to their original size when exhaling. The lungs expand, however, by only around 40%.

The huge swelling effect has been achieved in a simple way: MIL materials were immersed into solvents, and their cavities were filled and thus opened by entering solvent molecules. This made the structures grow, without breaking bonds and retaining the crystallinity of the materials. This process was monitored at the ESRF, using high-quality synchrotron radiation and the experimental results were combined with computer chemistry simulations.

This process can reversed by heating the solvated form the dry form is recovered. In this form, the material exhibited closed pores with almost no accessible porosity. Surprisingly, the same team published a paper last autumn where they showed that some gas molecules can close, but not open, the pores upon absorption. Moreover, the closed hydrated form demonstrates a remarkable selectivity in absorption of polar and nonpolar gases.

The next step for the team now is to investigate how hydrogen or green-house gases can be stored in these kinds of materials. This may open a door to ecological applications such as hydrogen cars or the capture of carbon dioxide in the near future.

Montserrat Capellas | alfa
Further information:
http://www.esrf.fr/news/pressreleases/nanoporous/

More articles from Materials Sciences:

nachricht Multitasking monolayers
25.07.2017 | Vanderbilt University

nachricht Flexible proximity sensor creates smart surfaces
25.07.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA mission surfs through waves in space to understand space weather

25.07.2017 | Physics and Astronomy

Strength of tectonic plates may explain shape of the Tibetan Plateau, study finds

25.07.2017 | Earth Sciences

The dense vessel network regulates formation of thrombocytes in the bone marrow

25.07.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>