A Versatile, high-throughput, Analytical Transmission Electron Microscope (VATEM)

Electron microscopes allow imaging and spectroscopy at resolution up to and including atomic resolution, and are key tools for materials characterisation. The highest spatial resolutions are found in the transmission electron microscope (TEM), which makes use of a very thin samples (nanometres or 10s of nanometres thickness) to minimise beam spreading.

The term "TEM", actually refers to a range of experimental techniques, including diffraction contrast imaging, high-resolution TEM (HRTEM), scanning TEM (STEM), energy-dispersive X-ray (EDX) spectroscopy mapping and electron energy-loss spectroscopy (EELS).

The aim of the current proposal is to procure a Versatile, high-throughput, Analytical TEM (VATEM) at the University of Oxford. The aim of the instrument is that it should be versatile and therefore able to address the widest possible range of materials science problems; it should be high-throughput maximising the science delivery; and it should be relatively easy to use to enable researchers to experience the capabilities of TEM methods and to develop expertise in the field.

It will be accessible to researchers ranging from undergraduates performing research projects to experienced academics.

The UK has long been a world-leader in TEM method development and application, with substantial investment in world-leading capabilities such as those at SuperSTEM (Daresbury) and ePSIC (Diamond Light Source) and the Rosalind Franklin Institute which provide specific, high-level capabilities. Such facilities are only sustainable with a supporting infrastructure of instruments located at university centres of excellence.

The instrument proposed here will form an important part of that infrastructure supporting regional and national research.

The VATEM has been specified to study the widest possible range of samples. The portfolio of science that the instrument will address is exemplified in this proposal in the fields of materials for energy storage and conversion, materials for nuclear energy and nanomaterials, but the potential breadth of application is much greater than this. Materials critical for applications in energy storage, photovoltaic, nuclear, catalytic, degradation resistant and semiconductor devices all have key properties controlled by their structure and chemistry at the nanoscale.

The imaging and spectroscopy methods available in a TEM can be used to determine structure and chemistry. There are, however, a number of challenges. Many such materials are either air-sensitive, electron-beam sensitive, or both.

Developments in MEMS technology further allows nanoscale structure and composition measurements under a variety of environments including cooling, heating, gases, anaerobic, liquids, optical, electrical and mechanical stimuli. The instrument has been designed to address these challenges.

The VATEM will be available researchers national and internationally who can demonstrate that the instruments capability will be meet a need in their research.