- Tytuł:
- The Influence of Boron Doping Concentration on $MgH_{2}$ Electronic Structure
- Autorzy:
-
Kurko, S.
Paskaš-Mamula, B.
Matović, Lj.
Grbović Novaković, J.
Novaković, N. - Powiązania:
- https://bibliotekanauki.pl/articles/1503283.pdf
- Data publikacji:
- 2011-08
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
31.15.A-
88.80.F-
88.30.R- - Opis:
- We have performed ab initio electronic structure calculations of $Mg_{1-x}B_{x}H_{2}$ compounds with different boron concentrations, ranging from x =0.0625 to 0.5. Full structural relaxation was performed in order to properly describe influence of dopant on host matrix. Results showed that there is a strong influence of boron concentration on structural and thermodynamic stability of compound. B-H bond length is substantially shorter then in Mg-H coordination polyhedron. Boron significantly contributes to density of states at Fermi level within energy gap. The width of boron electronic states heavily depends on boron concentration, causing reduction of energy gap of host $MgH_{2}$, and leading to metallic nature of compound with highest boron concentration. The predicted thermodynamic instability of compounds with higher boron concentration is in agreement with experimental findings that under similar stoichiometry, boron with magnesium forms only complex hydride, $Mg(BH_{4})_{2}$. It is also shown that existence of stable hydrides with $MgH_{2}$ rutile structure and small concentration of boron is possible in principle and that boron can be used to further destabilize $MgH_{2}$ in order to enhance its hydrogen sorption-desorption kinetics.
- Źródło:
-
Acta Physica Polonica A; 2011, 120, 2; 238-241
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł