Lithium adsorption on zigzag graphene nanoribbons

Abstract

We have studied the adsorption of Li atoms at the hollow sites of graphene nanoribbons (zigzag and armchair), graphene, and fullerenes by means of density functional theory calculations including local and semilocal functionals. The binding energy of a Li atom on armchair nanoribbons (of about 1.70 eV for LSDA and 1.20 eV for PBE) is comparable to the corresponding value in graphene (1.55 and 1.04 eV for LSDA and PBE, respectively). Notably, the interaction between Li and zigzag nanoribbons is much stronger. The binding energy of Li at the edges of zigzag nanoribbons is about 50% stronger than in graphene for the functionals studied here. While the charge transfer between the Li adatom and the zigzag nanoribbon significantly affects the magnetic properties of the latter providing an additional interaction mechanism that is not present in two-dimensional graphene or armchair nanoribbons, we find that the morphology of the edges, rather than magnetism, is responsible for the enhanced Li-nanoribbon interaction.

Rippling instabilities in suspended nanoribbons

“…As a classic example, the band gap in graphene nanoribbons (GNRs) is sensitive to edge type and ribbon width and in extreme cases determines the nature of the electronic transport, metallic or semiconducting [1][2][3][4][5][6] . The ribbon morphology serves as a crucial ingredient in quantifying these structure-property relations as it determines the nature and extent of edge functionalization 7,8 and also controls the overall mechanics 9,10 .…”

Metals on Graphene: Interactions, Growth Morphology, and Thermal Stability

“…Charge transfer upon metal adsorption on graphene has also been investigated by experiments [10][11][12][13][14][31][32][33][34][35][36][37]. Recent experimental studies showed that alkali adatoms adsorption on graphene donate their valence electron easily (i.e., 0.3~0.4 electrons) and act as good agents for n-doping of graphene [10][11][12][13][14][31][32][33][34][35][36][37].…”

“…The interaction between K adatoms on graphite also exhibited long range repulsive interactions from a STM study [14] but the coverage was very low and the temperature much lower so no ordered arrangements of the K adatoms were accessible. All the experiments [10,11,14] and the theoretical studies [31][32][33][34][35][36][37] showed that alkali adatoms adsorption on graphene donate their electrons easily. Therefore the interaction between alkali adatoms and graphene is mainly ionic, which is consistent with the conclusions of Liu et al [71][72][73]76] and other works [12,13,31,38].…”

“…Recent experimental studies showed that alkali adatoms adsorption on graphene donate their valence electron easily (i.e., 0.3~0.4 electrons) and act as good agents for n-doping of graphene [10][11][12][13][14][31][32][33][34][35][36][37]. By using the STM technique combined with density functional calculations, Song et al [10] studied cesium adsorption on graphene supported on a 6H-SiC(0001) substrate.…”

“…For example, recent studies [10][11][12][13][14][31][32][33][34][35][36][37] showed that alkali adatoms adsorption on graphene release their valence electron easily and act as good agents for n-doping of graphene. In addition to alkali metal adsorptions, research interest in transition and noble metal elements [38][39][40][41][42][43][44][45][46][47][48][49]53] or clusters [50][51][52][54][55][56][57] adsorbed on graphene continues to grow rapidly and broadens the range of applications from catalysis [65][66][67][68][69][70], spintronics [9,27,28], to nanomagnetic devices [26,27,[38][39][40][41]…”