M.Sc. Candidate Mr. Eyal Cohen
Understanding the structural properties of cesium lead bromide perovskite and their implication on spectral characteristics is crucial in the effort of enhancing their quantum efficiency .We use state of the art characterization methods on solution grown, ligand free, cesium lead bromide perovskite micro-crystals to show that not only the Br vacancies trap states are responsible for the spectral split seen at low temperatures, but also we suspect they act as nucleation sites for the growth of the Cs4PbBr6 phase. To pinpoint regions of interest along the microcrystals, we used Cathodoluminescence (CL) spectroscopy, which can precisely pinpoint the spatial location of each emission individually, along with ultra-fast time resolved cathodoluminescence (TRCL) to identify relaxation dynamics. Structural and compositional analysis of the CsPbBr3/Cs4PbBr6 interface, presents a different zone axis for each phase and agglomeration of precipitants which are rich in lead and poor in bromide, which add vacancy base luminescent sites to the perovskite phase.
Supervisor: Asst. Prof. Yehonadav Bekenstein
The lecture will take place in room 302, Meidan, for green pass holders, or via ZOOM.
Meeting ID: 995 9239 6977