Zeolites* are important industrial materials with complicated structures. They are widely used in washing powders, in catalysts to clean the exhaust gas from cars but also in oil refineries to produce petrol. Subtle differences in their structures have, however, profound effects on their properties and it is important to understand the structures in detail. This has been difficult as industrial zeolites are polycrystalline materials, where conventional single crystal methods cannot be used. Transmission electron microscopy (TEM) might help for these materials.
“Indeed we have recently solved solely by TEM two new zeolites structures. However, only relatively simple structures can be solved by TEM”, says Osamu Terasaki, professor in Structural Chemistry at Stockholm University, one of the authors of the article in Nature.
Various ways of solving the complicated structures have been developed, however none was successful for the present complicated zeolite. Researchers at Stockholm University¸ ETH (Die Eidgenössische Technische Hochschule) in Zürich, St Andrews in the UK and Hanbat University in Korea extended the limit very much by using a software developed by a group at ETH. The methods and their results have been published in the latest issue of Nature.
Electron microscopy (EM) has been used and developed at the Department of Physical, Inorganic and Structural Chemistry continuously since 1974.
“We are building an active EM centre by upgrading various electron microscopes, thanks to the Knut and Alice Wallenberg Foundation for a generous donation. We will continue development in crystallographic methodology for atomic-scale characterisation of complicated materials. By this we hope to improve the knowledge of the materials and thereby design better materials for the society”, says Osamu Terasaki.
The article “Complex zeolite structure solved by combining powder diffraction and electron microscopy” has been published in Nature on 02 November.
For further information, please contact:
Prof. Osamu Terasaki, Structural Chemistry, 46-8-162379 or terasaki@struc.su.se.
For more information about the EM Centre, please visit http://www.fos.su.se:80/em/
For a photograph of Prof. Osamu Terasaki, please contact Maria Sandqvist, University Relations, Stockholm University, phone + 46 8 16 13 77, email maria.sandqvist@eks.su.se
* From the two Greek words “zeos” and “lithos” meaning “boiling” and “a stone”. Named by the Swedish mineralogist A.F. Cronsted, who discovered the first zeolite mineral Stilbite in 1756.