Scientists investigate a new class of nanofiber with helium ion microscope

At HZB we often have interesting guests from abroad – and with challenging topics. I met two of them, Vitaly Datsyuk and Svitlana Trotsenko, on a sunny autumn day.

The first time Vitaly and Svitlana came to HZB in Wannsee, they were stopped at the gate. Both scientists work in the Physics Department of Freie Universität Berlin on a Ukrainian passport. But because the requisite application as required by the Foreign Trade and Payments Act hadn’t gone through, the two had to leave empty handed. And yet, this minor hiccup did not stop them from returning. In fact now, once a month, they are regular guests at the HZB CoreLab “Correlative Microscopy and Spectroscopy”.

Here, researchers can use the latest scanning electron and ion microscopes developed by ZEISS to produce nanoscale images of their materials. “The microscopy lab at HZB is the most important partner for us because only here do we find the suitable methods for studying our samples,” says Svitlana Trotsenko. The researchers used the helium ion microscope. This is a prototype from ZEISS, and one of the few in the world that the company has built so far.

Wanted: Materials that insulate heat

The two FU researchers are developing materials that are especially good at insulating heat. Such materials are in demand as facade insulation, for example. “The project is being funded by the Federal Ministry of Research and is of great economic interest. So, we are working very closely together with industrial partners,” Vitaly Datsyuk explains.

To reduce the thermal conductivity of such materials further – so that they insulate even better – the FU researchers are using electrospinning technology. They develop a new class of the nanofiber –based insulation materials which are easy to use and suitable for new construction as well as renovation of older buildings to improve energy using. Additionally they try to solve a problem with recycling polystyrene from waste materials. “Our technology is low cost, since it is based on renewable and waste sources”. With the help of the helium ion microscope, the researchers can reveal detailed images of the sample’s surface structure and determine what influence the porous nanostructures have on the thermal conductivity of the material.

Only at HZB: a prototype of ZEISS helium ion microscope

“The helium ion microscope is ideal because our samples consist of nonconductive materials, which cannot be studied with conventional ion microscopes,” Svitlana Trotsenko explains. So they are greatly pleased to be cooperating with HZB, and especially with such helpful supervision. “Katja Höflich is a very dedicated and far-sighted expert. When we discuss our experimental results together, it brings us an incredibly long way forward,” says Vitaly Datsyuk.