First-principles investigation on adsorption poisoning and heterogeneous nucleation mechanisms in Ca modified primary Mg2Si phase

0585033 - ÚFM 2025 RIV NL eng J - Článek v odborném periodiku
Huang, J. - Liu, S. - Friák, Martin - Du, Y.
First-principles investigation on adsorption poisoning and heterogeneous nucleation mechanisms in Ca modified primary Mg2Si phase.
Materials Today Communications. Roč. 39, Jun (2024), č. článku 108770. ISSN 2352-4928. E-ISSN 2352-4928
Grant CEP: GA ČR(CZ) GA22-22187S
Institucionální podpora: RVO:68081723
Klíčová slova: First-principles calculations * Heterogeneous nucleation * Adsorption * Interface properties
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 3.8, rok: 2022

We employed first-principles calculations to investigate the adsorption poisoning and heteroepitaxial nucleation
mechanisms in the Ca modification of the primary Mg2Si phase. The extensive computations considering various
factors such as lattice mismatch, interface energy, adsorption energy, charge density, work of adhesion, and
interface mechanical properties, as well as comparisons of interface stacking modes reveal that Ca modification
of the primary Mg2Si phase can occur through both adsorption poisoning and heteroepitaxial nucleation
mechanisms simultaneously. The adsorption poisoning mechanism implies that Ca preferentially adsorbs on the
Mg-terminated surfaces of Mg2Si(100) and Mg2Si(111). Meanwhile, the heteroepitaxial nucleation mechanism
indicates the nucleation interface of Mg2Si(100)//CaSi2(001), where the Mg2Si(100) surface is terminated by Si,
and the CaSi2(001) surface is terminated by Ca, with stacking modes of Si-Top and Si-Center. In addition, the
inclusion of Ca in the primary Mg2Si phase through heteroepitaxial nucleation not only leads to refinement of the
primary Mg2Si phase but also displays excellent interface mechanical properties, which suggests that Ca can be
considered as an optimal modifier for the primary Mg2Si phase. This study provides a fundamental insight into
the role of Ca in modifying the primary Mg2Si phase and has potential implications for the development of Si-containing magnesium alloys.
Trvalý link: https://hdl.handle.net/11104/0352807