Best electron microscope in the world for Utrecht University

Utrecht University has brought into use the, at this moment, most advanced electron microscope of its kind. It enables scientists to image individual atoms in nanoparticles, and offers possibilities to develop new sustainable materials.

Spectra300

On 24 March 2020, a new, 3.6 metres high microscope was carried into the Androclus building on the Utrecht Science Park. For nine months, the supplier has prepared it and in the week prior to Christmas, it was delivered. Another two months later, the Spectra300, the world’s most advanced electron microscope, is actually been taken into use on 1 March 2021. Very custom-made indeed.

Facility manager Chris Schneijdenberg of the Utrecht University Electron Microscopy Center is happy. “With this microscope, we can make images with an unprecedentedly high resolution. Researchers can look at the configuration of atoms in structures at the nano scale.”

These configurations are important in order to understand the chemical and physical characteristics of materials and to develop new materials. Schneijdenberg: “The microscope can detect, image and characterize even the lightest elements like oxygen, nitrogen and carbon. With that knowledge, for example better and more energy efficient batteries, solar panels and electronic screens can be designed.”

It is really fantastic that we can now distinguish so much detail ourselves, and not have to travel abroad to gain such images.

Head of the electron microscopy center Marijn van Huis adds to that: “We are conducting research on many materials that are extraordinary because they have traits that are unique to nanoparticles. 2D-materials like graphene have a thickness of just a few atoms and for the characteristics of such materials, it is very important where the atoms are located and which chemical elements are present. It is really fantastic that we can now distinguish so much detail ourselves, and not have to travel abroad to gain such images.”

Use every electron

The machine is at the moment unique in the world, says Schneijdenberg. “The Spectra300 is what we call ‘double corrected’ for lens errors. We can use the microscope in two ways. Sometimes we make a super small electron beam as narrow as a twentieth of a nanometer, and, using this ‘probe’, scan the surface of the sample. In other situations we make a wide bundle to be able to look at the whole sample at once. For both ways of observation, this microscope provides a top-resolution.”

We can the Spectra300 electron beam super small, but we can also make a wide bundle. For both ways of observation, this microscope provides a top-resolution.

The number 300 means that electrons in the column are accelerated with a high voltage of 300 kiloVolt. Schneijdenberg: “They rage through the investigated material at ultrahigh speed. The machine also has an extremely sensitive so-called direct electron detector that uses almost every electron to make the image. Consequently, we are now able to look at soft and radiation sensitive materials as well.” For that matter, the price of the microscope seems quite low: it cost 5 million euros in total. Especially the camera with energy filter was expensive, according to Schneijdenberg. “1.8 million.”

During the months to come, nano-scientists of Utrecht University will start using the Spectra300 in their research. Some chemists and physicists already have plans. Van Huis: “A great advantage of this technique is that you can work with very small amounts. On top of that, we also have special sample holders in order to study the material during heating, or in liquid or gas environments.”

National facility

After a few months’ testing period, the electron microscope will mid-year be available for material scientists and nano scientists from all over the Netherlands. Schneijdenberg: “It will be taken up into the Netherlands Electron Microscopy Infrastructure, the NEMI Roadmap, a national facility.”

Operating the Spectra300 will by the way for the first time at Utrecht University be done with the help of two operators. Scheijdenberg: “With other microscopes, we teach our researchers to do the work themselves, but the Spectra300 is so full of advanced detectors, electronics and software. You need to be an expert to be able to work with it.”