SuperSTEM facility opens at Daresbury

Published Monday 15 January 2012

A new state-of-the-art materials facility managed by the SuperSTEM consortium, which is led by the University of Leeds, has been opened at the STFC Daresbury Laboratory in Cheshire.

The £4.5 million EPSRC National Facility for Aberration-Corrected Scanning Transmission Electron Microscopy (STEM) will allow scientists to see the properties of materials at the atomic level by providing access to cutting-edge instrumentation and state-of-the-art data analysis. It will also help researchers from universities across the UK gain expertise and training in electron microscopy.

Aberration-corrected scanning transmission electron microscopy (STEM) is a key tool for the characterisation of nanostructures and nanotechnological devices. It uses computer-controlled lens correctors to form a probe of electrons smaller than the width of an atom. This is used to image nanostructures in atomic projection and also to spectroscopically analyse the type of atom and its chemical bonding.

Access to an aberration-corrected STEM facility is a key requirement for many areas of physics, chemistry, biochemistry and materials science. The new EPSRC National Facility for aberration-corrected STEM will provide ‘free at point of use’ access to cutting-edge instruments for EPSRC-funded researchers within the UK, and, also for non-EPSRC and commercial users within the utilisation limits of the facility.

EPSRC's head of physical sciences, Dr Andrew Bourne said: "This national facility will provide UK researchers with an internationally renowned resource in which they can carry out exciting experiments at the nanoscale. EPSRC is pleased to be working with the SuperSTEM Consortium and the Science and Technology Facilities Council (STFC) to open up this new vista for microscopy."

Established in 2001, SuperSTEM was the first group in Europe to adopt aberration corrected STEM.
The instruments are situated at the STFC Daresbury Laboratories in a purpose-built low-vibration laboratory and can be used for a range of atomic resolution imaging and analysis techniques over a range of incident electron beam energies.

Users of the EPSRC National Facility will also have access to other specialised aberration-corrected instruments at both the consortium universities (Leeds, Glasgow, Liverpool, Manchester and Oxford) and external partner universities, such as Cambridge, Sheffield and Warwick, where required. These will provide access to additional important capabilities for STEM users.

Researchers at Leeds, led by Dr Andy Brown in the Institute for Materials Research, have used SuperSTEM to visualise the way iron is stored and accessed within biological organisms (including humans) in the form of ferritin molecules. Ferritin molecules contain a nanometre-sized mineral core containing a few thousand iron atoms surrounded by a shell of proteins.

Images of the molecules acquired by Dr Brown and colleagues revealed that this core is made up of a number of different crystallites, arising from the symmetry of the protein shell that enables biomineralisation of the iron. This has many implications ranging from the fundamental processes of crystallisation in biological systems, through to the understanding of iron-storage processes in organisms as well as medical imaging using MRI.

For further information:
Contact Professor Rik Brydson, Institute for Materials Research, SPEME, Faculty of Engineering and Centre for Molecular Nanoscience, School of Chemistry at the University of Leeds or visit the SuperSTEM website www.superstem.org.