Direct observation of site-selective hydrogenation and spin-polarization in hydrogenated hexagonal boron nitride on Ni(111)
Autor: | Shiro Entani, Natalia S. Mikhaleva, Xia Sun, Yoshihiro Matsumoto, Hiroshi Naramoto, Pavel V. Avramov, Yasushi Yamauchi, Alexander A. Kuzubov, Manabu Ohtomo, Seiji Sakai |
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Rok vydání: | 2017 |
Předmět: |
Materials science
Spin polarization Hydrogen chemistry.chemical_element Nanotechnology 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences XANES 0104 chemical sciences Crystallography chemistry.chemical_compound Hydrogen storage chemistry Boron nitride General Materials Science Density functional theory 0210 nano-technology Electronic band structure Boron |
Zdroj: | Nanoscale. 9:2369-2375 |
ISSN: | 2040-3372 2040-3364 |
Popis: | We report the structural analysis and spin-dependent band structure of hydrogenated boron nitride adsorbed on Ni(111). The atomic displacement studied by using the normal incidence X-ray standing wave (NIXSW) technique supports the H–B(fcc):N(top) model, in which hydrogen atoms are site-selectively chemisorbed on boron atoms and N atoms remain on top of Ni atoms. The distance between the Ni plane and nitrogen plane did not change after hydrogenation, which implies that the interaction between Ni and N is 3d–π orbital mixing (donation and back-donation) even after hydrogenation of boron. The remaining π* peaks in near-edge X-ray absorption fine structure (NEXAFS) spectra are a manifestation of the rehybridization of sp2 into sp3 states, which is consistent with the N–B–N bonding angle derived from NIXSW measurement. The SPMDS measurement revealed the spin asymmetry appearing on hydrogenated h-BN, which was originated from a π related orbital with back donation from the Ni 3d state. Even though the atomic displacement is reproduced by the density functional theory (DFT) calculation with the H–B(fcc):N(top) model, the experimental spin-dependent band structure was not reproduced by DFT possibly due to the self-interaction error (SIE). These results reinforce the site-selective hydrogenation of boron and pave the way for efficient design of BN nanomaterials for hydrogen storage. |
Databáze: | OpenAIRE |
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