Electronics and Magnetism of Patterned Graphene Nanoroads

Abstract

Individual ribbons of graphene show orientation-dependent electronic properties of great interest, yet to ensure their perfect geometry and integrity or to assemble free ribbons into a device remains a daunting task. Here we explore, using density functional theory, an alternative possibility of "nanoroads" of pristine graphene being carved in the electrically insulating matrix of fully hydrogenated carbon sheet (graphane). Such one-dimensional entities show individual characteristics and, depending upon zigzag (and their magnetic state) or armchair orientation, can be metallic or semiconducting. Furthermore, the wide enough zigzag roads become magnetic with energetically similar ferro- and antiferromagnetic states. Designing magnetic, metallic, and semiconducting elements within the same mechanically intact sheet of graphene presents a new opportunity for applications.

Constructing metallic nanoroads on a MoS2monolayer via hydrogenation

“…Our DFT calculations are carried out using the plane wave code Vienna ab initio simulation package (VASP) 22 within the framework of DFT with the generalized gradient approximation 20 (GGA). Spin-polarized calculations using the projector augmented wave method with the Perdew-Burke-Ernzerhof functional (PAW-PBE) 23 and a cutoff energy of 400 eV are adopted.…”

“…Both values are comparable to the • -• * electronic transition of 8 eV for Si-H bond in hydrogenated Si surface. 30 The relatively large 20 separation of the bonding state and antibonding state suggests that the strong stability of H binding is able to prevent H desorption under photonic or electronic excitation for normal electronics applications.…”

Elastic properties of hybrid graphene/boron nitride monolayer

“…The h-BN domain size effect then can be represented by the h-BN concentration x in the model as (B 3 N 3 ) x (C 6 ) 1−x where (B 3 N 3 ) and (C 6 ) denote the nanodomain structure of h-BN monolayer and graphene, respectively. The proposed domain size effect model (B 3 N 3 ) x (C 6 ) 1−x is based on the results of previous studies of B x C y N z layered structures [11], layers and nanotubes [12,13], quantum dots and nanorods [14], and monolayer nanohybrids [15]. It is a general belief that the h-BN segregates in the h-BNC, and the system gains lower energy, larger band gap, and better thermal stability after phase segratation [1,12,15].…”

Nano-Engineering of Graphene and Related Materials

“…Experimental studies also reveal the semimetalinsulator transition in graphene after hydrogenation, which is then recoverable through structural annealing (Elias et al, 2009). When rationally designed, this reversible engineering on graphene has further potential applications in designing functional nanoscale materials and devices, such as hydrogen storage materials and patterned nanoelectronics (Singh & Yakobson, 2009;Lee & Grossman, 2010). The fully hydrogenated graphene -graphane -offers a high hydrogen storage weight ratio up to 7.7 wt % that is able to meet US Department of Energy (DOE)'s 2010 goal (6 wt %).…”