Abstract
To explore the effect of boron on the high-temperature oxidation resistance of WSi2 in atomic scale, the stability of WSi2 surfaces were firstly investigated by the first-principles calculations. The calculated surface energies of low-index stoichiometric surfaces show that WSi2(110) surface has thermodynamic stability. Then the segregation behavior of boron element in the WSi2(110) surface was discussed, and the result indicates that the boron can spontaneously segregate from interior to surface, which improves the stability of WSi2(110) surface through the strong bonding interaction between B and its neighboring Si atoms. Finally, the adsorption behaviors of oxygen atom on WSi2(110) surface with and without B doping are analyzed and the electronic properties of those adsorption structures are discussed. The preference adsorption position of pure WSi2(110) surface for oxygen atom is hollow site, and the electronic structures illustrate that oxygen atom preferentially tend to bond with Si atom instead of W atom. While the most favorable position on WSi2B0.08(110) surface is bridge site for oxygen atom. The orbital hybridizations between adsorbed oxygen atom, B and Si atoms lead to the formation of B2O3 or borosilicate, which is beneficial to the high-temperature oxidation resistance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.