Speaker: Sara Bals, University of Antwerp

Panelist: Haixia (Alice) Zhang, Peking University

Time: 8:00 p.m., April 21, 2023, GMT+8

Venue: Long press to identify the QR code and jump to the webpage!


Abstract:

Electron tomography enables one to measure the morphology and composition of nanostructures in three dimensions (3D), even at atomic resolution. However, an emerging challenge is to fully understand the connection between the 3D structure and properties under realistic conditions, including high temperatures as well as in the presence of liquids and gases.

Our recent experiments demonstrate the progress that can be obtained by accelerating both the acquisition and reconstruction during electron tomography. In this manner, we were able to perform a dynamic characterisation of shape changes of metal nanoparticles at high temperatures. Moreover, we measured the elemental diffusion dynamics of individual anisotropic bimetallic nanoparticles in 3D and determined the effect of parameters such as type of interfacial facets, aspect ratio, shape and presence of defects.

Finally, by combining aberration corrected electron microscopy with a quantitative interpretation, we can provide quantitative measurements of the coordination numbers of the surface atoms of catalytic nanoparticles at high temperatures and in gaseous environments.

Biography:

Sara Bals studied Physics at the University of Antwerp from 1995-1999. She obtained her PhD in 2003 with greatest distinction and special honours by the jury. From 2003-2004, she did postdoctoral work at the National Center of Electron Microscopy in Berkeley, USA. After returning to UAntwerp, she became an Assistant Professor in the Physics Department. In 2018 she was promoted to Full Professor. She is currently the spokesperson of EMAT, consisting of 7 principal investigators, about 25 postdoctoral researchers and more than 30 PhD students. Moreover, she is the coordinator of the “Nanolab” Centre of Excellence at the host institution, composed of 6 research groups.

She was awarded an ERC Starting grant in 2012, an ERC Consolidator grant in 2018, received the award "Laureate of the Academy for Natural Sciences" by the Royal Flemish Academy in 2016, became Francqui research professor in 2017 and was elected as member of the Royal Flemish Academy of Belgium for Science and the Arts in 2020. She received the European Microscopy Award in 2020 and the ACS Nano Lectureship award in 2021.

Source: iCANX