resumo
The interest in understanding the interaction between graphene and atoms that are adsorbed on its surface (adatoms) spans a wide range of research fields and applications, for example, to controllably change the properties of graphene in electronic devices or to detect those changes in graphene-based sensors. We present a density functional theory study of the interaction between graphene and Hg adatoms. Binding energy, electronic structure and electric field gradient (EFG) were calculated for various high-symmetry atomic configurations, from isolated adatoms to a continuous Hg monolayer. Hg as isolated adatom was found to be the most stable configuration, with a binding energy of 188 meV. Whereas isolated adatoms have a minor effect on the electronic structure of graphene (small acceptor effect), Hg monolayer configurations induce a metallic state, with the Fermi level moving well above the Dirac point (donor behavior). Based on the EFG calculated for the various configurations, we discuss how hyperfine techniques (perturbed angular correlation spectroscopy, in particular) can be used to experimentally study Hg adsorption on graphene.
categoria
Materials Science, Multidisciplinary
autores
Fenta, AS; Amorim, CO; Goncalves, JN; Fortunato, N; Barbosa, MB; Araujo, JP; Houssa, M; Cottenier, S; Van Bael, MJ; Correia, JG; Amaral, VS; Pereira, LMC
nossos autores
Abel Eduardo Silva Fenta
Colaborador
Carlos Amorim
Investigador Auxiliar
João Nuno Santos Gonçalves
Investigador Júnior
Nuno Fortunato
Bolseiro de investigação
Vitor Brás Sequeira Amaral
Professor CatedráticoGrupos
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G6 - Materiais Virtuais e Inteligência Artificial
agradecimentos
This work was funded by the Portuguese Foundation for Science and Technology (FCT) (CERN-FIS-NUC-0004-2015, CERN-FIS-PAR-0005-2017, POCI-01-0145-FEDER-032527, SFRH/BPD/82059/2011, SFRH/BD/93336/2013 and SFRH/BD/84743/2012), by CICECO-Aveiro Institute of Materials (POCI-01-0145-FEDER-007679)-FCT reference (UID/CTM/50011/2013), by the Fund for Scientific Research Flanders (FWO) and the KU Leuven BOF (CREA/14/013, STRT/14/002).