Applied Surface Science, Vol.311, 9-13, 2014
Effects of silver adatoms on the electronic structure of silicene
This paper presents the adsorption of Ag adatoms on silicene surface using first-principles plane wave calculations within density functional theory. It is obtained that silver adatoms form strong bonds with the silicene yielding significant binding energies. The bare silicene, which is a nonmagnetic semimetal, becomes either nonmagnetic metal or semiconductor depending on the number of adsorbed silver atoms. Because of the charge transfer from adatoms to silicene, bonding and antibonding pi bands crossing linearly at the Fermi level shift 0.35 eV below the Fermi level for both single and trimer Ag adsorption. Ag dimer adsorbed silicene becomes a narrow gap semiconductor with E-g = 0.112 eV. (C) 2014 Elsevier B.V. All rights reserved.