Hydrogen physisorption channel on graphene: a highway for atomic H diffusion. (11th March 2019)

• Record Type: Journal Article
• Authors: González-Herrero, H; Cortés-del Río, E; Mallet, P; Veuillen, J-Y; Palacios, J J; Gómez-Rodríguez, J M; Brihuega, I; Ynduráin, F
• Is Part Of: 2D materials. Volume 6:Number 2(2019)
• Publication Date: 2019-03-11
• Subjects: graphene -- atomic hydrogen -- diffusion -- scanning tunneling microscopy -- density functional theory; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/ab03a0
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: We study the adsorption of atomic hydrogen on graphene by combining scanning tunneling microscopy experiments and first principle calculations. Our results reveal the existence of a physisorption channel over the graphene layer, dominated by van der Waals forces and thus homogeneous over the whole atomic lattice, where atomic hydrogen can move freely. Such physisorption channel is essential to understand the final configuration of hydrogen atoms chemisorbed on graphene. We find that ~95% of chemisorbed H atoms form non-magnetic dimers even for very dilute concentrations (<0.1%) deposited at low temperatures (140 K). Our data shows that this scenario holds from mono to multilayers graphene on SiC(0 0 0 − 1), SiC(0 0 0 1) and graphite.