Impact of d-states on transition metal impurity diffusion in TiN.

Autor: Nayak GK; Department of Materials Science, Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700, Leoben, Austria. nayak@mch.rwth-aachen.de.; Materials Chemistry, RWTH Aachen University, Kopernikusstraße 10, 52074, Aachen, Germany. nayak@mch.rwth-aachen.de., Holec D; Department of Materials Science, Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700, Leoben, Austria., Zelený M; Faculty of Mechanical Engineering, Institute of Materials Science and Engineering, Brno University of Technology, Technická 2896/2, 616 69, Brno, Czech Republic.
Jazyk: angličtina
Zdroj: Scientific reports [Sci Rep] 2023 May 22; Vol. 13 (1), pp. 8244. Date of Electronic Publication: 2023 May 22.
DOI: 10.1038/s41598-023-34768-7
Abstrakt: In this work, we studied the energetics of diffusion-related quantities of transition-metal impurities in TiN, a prototype ceramic protective coating. We use ab-initio calculations to construct a database of impurity formation energies, vacancy-impurity binding energies, migration, and activation energies of 3d and selected 4d and 5d elements for the vacancy-mediated diffusion process. The obtained trends suggest that the trends in migration and activation energies are not fully anti-correlated with the size of the migration atom. We argue that this is caused by a strong impact of chemistry in terms of binding. We quantified this effect for selected cases using the density of electronic states, Crystal Orbital Hamiltonian Population analysis, and charge density analysis. Our results show that the bonding of impurities in the initial state of a diffusion jump (equilibrium lattice position), as well as the charge directionality at the transition state (energy maximum along the diffusion jump pathway), significantly impact the activation energies.
(© 2023. The Author(s).)
Databáze: MEDLINE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje