Morphing Graphene-Based Systems for Applications: Perspectives from Simulations

Abstract

Graphene, the one-atom-thick sp 2 -hybridized carbon crystal, displays unique electronic, structural and mechanical properties, which promise a large number of interesting applications in diverse high-tech fields. Many of these applications require its functionalization, e.g., with substitution of carbon atoms or adhesion of chemical species, creation of defects, modification of structure or morphology, to open an electronic band gap to use it in electronics, or to create 3D frameworks for volumetric applications. Understanding the morphology-properties relationship is the first step to efficiently functionalize graphene. Therefore, a great theoretical effort has been recently devoted to model graphene in different conditions and with different approaches involving different levels of accuracy and resolution. Here, we review the modeling approaches to graphene systems, with a special focus on atomistic level methods, but extending our analysis onto coarser scales. We illustrate the methods by means of applications with possible potential impact.

Interfacing Graphene-Based Materials With Neural Cells

“…With its promising properties, G has shown great potential in various applications, and the number of computational studies devoted to it is in constant growth (Cavallucci et al, 2016 ). Classical MD simulations (i.e., based on a classical physics description of atom-atom interactions) produced in the recent years a large amount of results on the interaction between G-based materials and biomolecules.…”

Engineering 3D Graphene-Based Materials: State of the Art and Perspectives

“…Similar effects were obtained by intercalating metal clusters in between graphene and an insulating substrate [103], where the preferential adhesion of the radicals was observed in proximity of the metal cluster. The enhancement of reactivity (towards aryl radicals) is also observed on non-metallic substrates, such as patterned SiO 2 [104] and on the protruding areas of the natural moiré corrugation lattice of monolayer graphene on SiC (towards atomic hydrogen [26]). In these cases, it is attributed to the curvature [24].…”

“…In summary, the need for large GC for gas or electrolytes adsorption calls for large SSA and low ρ [10,55], undermining the structural stability. On the other hand, volumetric capacity (VC) increases with ρ, and the pore size must be tuned to the adsorbed fluid [26]. Clearly, the capability of finely controlling the structural parameters has a main role [56].…”

“…The electronic structure is strongly affected by these defects, since Si dangling bonds produce electronic states localized near the Fermi level [113]. While all of the different carbon layers on SiC display charge inhomogeneities following a regular nano-pattern induced by the interaction with the substrate, either mediated by the hybridization, by the corrugation or by the vacancies in the intercalation coverage, only the GML was tested on its reactivity, showing selective H adhesion on the crests [26]. On the other hand, the localised electronic states forming on the QFMLG in corresponding of H-vacancies have various sizes and shapes, depending on the number and relative location of vacant sites and their energy is organized in groups of levels near the Fermi energy [113], indicating a possible propensity to electrophile attack.…”

“…Recently, a brand new branch of investigation has stemmed from graphene in-plane large mechanical strength and elasticity [3], coupled to out of plane flexibility [5]: controlled local strain would create pseudo-magnetic fields [19], besides band-gap opening and other specific electronic structure modifications [20,21] with interesting applications in nano-electronics and photonics; both in-plane (strain [22]) and out-of-plane (rippling [23]) mechanical alterations were shown to locally change chemical reactivity opening the way to controlled chemical nano-patterning [24,25]. Interestingly, all of the suggested modifications correspond to controlled disruption of the perfect symmetry of the crystal in a different way, which leads to viewing grapheme-rather than a single material-as a sort of morphable platform to build a class of slightly different materials suitable to specific purposes [26,27].…”