MEMS Seminar: Understanding of Energy Material BiCuSeO and Lattice Dynamics Effects of Dislocations
Wednesday, December 7, 2016 - 12:00pm to 1:00pm
Professor Ben Xu
BiCuSeO is a novel material that has attracted interest for both thermoelectric and photo-catalytic applications.This talk will be composed of two parts. Firstly, we will introduce BiCuSeO, which has the same intrinsic hetero-layered structure as its counterpart in iron-based superconductor. This specific layered structure can “boost” both its thermoelectric and photo-catalytic properties, which is observed in experiments and will be explained based on DFT calculation. More Generally, we would like to propose a new “hetero-transport” mechanism, which can be benefit photo-catalytic materials. Secondly, we will discuss the phonon interaction with dislocations inside the materials, which has not been properly addressed since early works in the 1950s, but was shown to be of significant importance to thermo-electric materials. Here, we show how phonons of different frequencies are scattered by a dislocation, using our own developed spectral energy density and interface scattering codes.
Dr. Xu Ben finished his undergraduate and master study in Central South University and Tsinghua University of China, working on transmission electron microscopy. Then he moved to University of Antwerp, worked with Professor Francois Peeters and Milosevic Milorad, using Ginzburg-Landau method and Gorkov’s green function to study the vortex states in superconductors. After that, he began his postdoc with David Rodney in CNRS, Grenoble using molecular dynamics to study the twinning effects in HCP metal. He joined School of Materials Science and Engineering in Tsinghua University since 2013. His main research interest is multiscale simulations of materials, especially the phonon properties, the defects evolution and materials genome.
Lunch will be served starting at 11:30 am.