ELFT HÍRADÓ

[Szeminárium koordinátor <szfi-seminar AT wigner.mta.hu>]

WIGNER SZFI Seminar

In-situ observation of the reversible electrochemical deposition of Fe in transmission electron microscopy

Ulrike Wolff
Leibniz Institute for Solid State and Materials Research, Institute for Metallic Materials, Dresden, Germany

Tuesday, 16 October 2018 10:00, KFKI Campus, Bldg. 1, 2nd floor, Conference Room

Materials science applications benefit largely from both the spatial resolution available with liquid cell transmission electron microscopy (TEM) and its temporal resolution, which allows reaction kinetics and mechanisms to be probed. Electrochemical processes provide an excellent example with in-situ TEM observations possible in a liquid cell that is filled with an electrolyte. Nucleation and growth of metals, catalytic reactions, nanoparticle self-assembly at liquid interfaces are just a few examples of the wide range of possibilities to use an in-situ TEM electrodeposition cell.

We are interested in the electrodeposition of Fe, which has regained increasing attention because of the unique catalytic, electronic, and magnetic properties of Fe nanostructures. Tailored shapes of Fe nanoparticles and self-termination phenomena in ultrathin films are currently discussed with regard to the role of hydrogen evolution that accompanies Fe electrodeposition, but the detailed atomistic processes involved are still under debate. During the current work to be presented, the initial growth stages of in-situ electrochemical Fe deposition in a TEM liquid cell were investigated. The experiments were performed in collaboration with the Department for Nanostructured Materials, Jožef Stefan Institute, Ljubljana, Slovenia. We have successfully observed for the first time the in-situ Fe deposition-dissolution process in a TEM liquid cell and affirmed that the Fe particles grow through electrochemical deposition rather than by virtue of the electron beam. In the presentation, the nucleation, morphology, and composition of the deposited Fe particles will be discussed.

 

Everyone is welcome to attend.

János Asbóth
szfi-seminar AT wigner.mta.hu