Next Article in Journal
Preparation and Characterization of Extruded Composites Based on Polypropylene and Chitosan Compatibilized with Polypropylene-Graft-Maleic Anhydride
Previous Article in Journal
Au3+/Au0 Supported on Chromium(III) Terephthalate Metal Organic Framework (MIL-101) as an Efficient Heterogeneous Catalystfor Three-Component Coupling Synthesis of Propargylamines
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessArticle
Materials 2017, 10(2), 103;

First-Principles Study of Vacancies in Ti3SiC2 and Ti3AlC2

School of Physics and Engineering, Henan University of Science and Technology, Luoyang 471003, China
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
Department of Electrical Engineering, University of California, Los Angeles, CA 90095, USA
Authors to whom correspondence should be addressed.
Academic Editor: Duncan H. Gregory
Received: 23 December 2016 / Revised: 18 January 2017 / Accepted: 23 January 2017 / Published: 25 January 2017
Full-Text   |   PDF [3446 KB, uploaded 25 January 2017]   |  


MAX phase materials have attracted increased attention due to their unique combination of ceramic and metallic properties. In this study, the properties of vacancies in Ti3AlC2 and Ti3SiC2, which are two of the most widely studied MAX phases, were investigated using first-principles calculations. Our calculations indicate that the stabilities of vacancies in Ti3SiC2 and Ti3AlC2 differ greatly from those previously reported for Cr2AlC. The order of the formation energies of vacancies is VTi(a) > VTi(b) > VC > VA for both Ti3SiC2 and Ti3AlC2. Although the diffusion barriers for Ti3SiC2 and Ti3AlC2 are similar (~0.95 eV), the properties of their vacancies are significantly different. Our results show that the vacancy–vacancy interaction is attractive in Ti3AlC2 but repulsive in Ti3SiC2. The introduction of VTi and VC vacancies results in the lattice constant c along the [0001] direction increasing for both Ti3SiC2 and Ti3AlC2. In contrast, the lattice constant c decreases significantly when VA are introduced. The different effect of VA on the lattice constants is explained by enhanced interactions of nearby Ti layers. View Full-Text
Keywords: MAX phases; vacancies; diffusion barrier; density functional theory MAX phases; vacancies; diffusion barrier; density functional theory

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Wang, H.; Han, H.; Yin, G.; Wang, C.-Y.; Hou, Y.-Y.; Tang, J.; Dai, J.-X.; Ren, C.-L.; Zhang, W.; Huai, P. First-Principles Study of Vacancies in Ti3SiC2 and Ti3AlC2. Materials 2017, 10, 103.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top