SEMINAR LMGP - 28.04.2020 - Damir PINEK
Shedding light on the electronic structure of Mn+1AXn nanolamellar carbides
Damir PINEK
PhD student at LMGP
Abstract
The Mn+1AXn, or “MAX” phases, where M is an early transition metal, A belongs to group 13-16 and X is C or N, are a class of nano-layered compounds that triggered strong interest from the material science community for their unique combinations of metal-like and ceramic-like properties [1]. They are also precursors for MXENES, a whole family of two dimensional carbides [2], notably sought for energy storage developments [3].
Despite MAX phases’ attractiveness regarding a wide range of applications, some of their fundamental features are yet to be fully understood [4], notably regarding the relationship between their electronic structure, anisotropies and transport properties.
In this talk we present the methodology followed to experimentally determine the morphology of the electronic states (e.g. Band structure and Fermi surface) of 3 phases: Cr2AlC, V2AlC and Ti3SiC2 [5-8]. Angle resolved photoemission spectroscopy (ARPES) experiments carried out on single crystals grown in Grenoble were consistently compared with the output of density functional theory (DFT) calculations. Then, we will go on with the description of a rigid band model that describes the electronic structure of all M2AC, or “211” MAX phases [9,10]. Finally, we will briefly introducing the magnetic derivatives of MAX phases: iMAX and 4473 phases [11,12].