Oxygen adsorption on ideal ZrB2 and ZrC surfaces

Chunyu Cheng, Wei Xie, Hejun Li, Qiangang Fu

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

To understand the initial oxidation of ZrB2 and ZrC, the adsorption behaviors of an O2 molecule on ideal ZrC (1 1 1) and ZrB2 (0 0 0 1) surfaces were investigated by first-principle calculation, and thermal gravimetric and differential scanning calorimetry test was executed. The results reveal that the initial oxidation temperature of ZrC was 210 °C, while that of ZrB2 was up to 500 °C since the adsorption energies of O2 molecule on Zr–ZrC surface was higher than that on Zr–ZrB2 surface. Meanwhile, the adsorbed O2 molecule affected the C atom bonding with the oxidized Zr atom in O–Zr–ZrC, while the B atom bonding with oxidized Zr atom in O–Zr–ZrB2 underwent little influence. Besides, the higher adsorption energy was obtained in O–C–ZrC than in O–B–ZrB2, implying that the C atom in C–ZrC might be oxidized more easily than the B atom in B–ZrB2. In addition, big holes (C vacancies) were formed when O2 molecule adsorbed on the C–ZrC surface because of the generation of C–C dimer and C–O bond, which led to that the next O2 molecule might penetrate the Zr atomic layer and react with the Zr atoms. While O2 molecule doped into the B atomic layer in B–ZrB2, and more O2 molecules might be adsorbed on the B–ZrB2 surface to generate a B2O3 structure to protect the inner material.

Original languageEnglish
Article number154655
JournalJournal of Alloys and Compounds
Volume830
DOIs
StatePublished - 25 Jul 2020

Keywords

  • First-principle study
  • Initial oxidation
  • Oxygen adsorption
  • ZrB
  • ZrC

Fingerprint

Dive into the research topics of 'Oxygen adsorption on ideal ZrB2 and ZrC surfaces'. Together they form a unique fingerprint.

Cite this