Theoretical study on Si-doped hexagonal boron nitride (h-BN) sheet: Electronic, magnetic properties, and reactivity

• Si-doping severely deforms the geometrical structures of the h-BN sheet.
• The band gap of the h-BN sheet is greatly decreased after Si-doping.
• The reactivity of the h-BN sheet to some common gas molecules is enhanced in various ways.

The properties and reactivity of Si-doped hexagonal boron nitride (h-BN) sheets were studied using density functional theory (DFT) methods. We find that Si impurity is more likely to substitute the boron site (SiB) due to the low formation energy. Si-doping severely deforms h-BN sheet, resulting in the local curvature changes of h-BN sheet. Moreover, Si-doping introduces two spin localized states within the band gap of h-BN sheet, thus rendering the two doped systems exhibit acceptor properties. The band gap of h  -BN sheet is reduced from ∼4.70 eV∼4.70 eV to 1.24 (for SiB) and 0.84 eV (for SiN), respectively. In addition, Si-doped one exhibits higher activity than pristine one, endowing them wider application potential.