We study the effect of long-range disorder created by charge impurities on the carrier density distribution of graphene-based heterostructures. We consider heterostructures formed by two graphenic sheets [either singlelayer graphene (SLG) or bilayer graphene (BLG)] separated by a dielectric film. We present results for symmetric heterostructures SLG-SLG and BLG-BLG, and hybrid ones BLG-SLG. As ...

Graphene sheets have been exfoliated from bulk graphite using high energy wet milling in two different solvents that were 2-ethylhexanol and kerosene. The milling process was performed for 60 h using a planetary ball mill. Morphological characteristics were investigated using scanning electron microscope (SEM) and transmission electron microscope (TEM). On the other hand, the structural charact...

Using friction force microscopy, we compared the nanoscale frictional characteristics of atomically thin sheets of graphene, molybdenum disulfide (MoS2), niobium diselenide, and hexagonal boron nitride exfoliated onto a weakly adherent substrate (silicon oxide) to those of their bulk counterparts. Measurements down to single atomic sheets revealed that friction monotonically increased as the nu...

Graphene is a single 2-dimensional atomic layer of hexagonally packed carbon atoms. Graphene has a unique combination of thermal, mechanical, and electronic properties, making it a useful tool for learning new physics as well as a material with high potential for applications. Bilayer graphene (2LG) and trilayer graphene (3LG) share many of the interesting properties of its monolayer relative, ...

Successfully integrating graphene in standard processes for applications in electronics relies on the synthesis of high-quality films. In this work we study Low Pressure Chemical Vapor Deposition (LPCVD) growth of bilayer graphene on the outside surface of copper enclosures. The effect of several parameters on bilayer growth rate and domain size was investigated and high-coverage bilayers films...

We develop a theory for density, disorder, and temperature-dependent electrical conductivity of bilayer graphene in the presence of long-range charged impurity scattering and short-range defect scattering, establishing that both contribute significantly to determining bilayer transport properties. We find that although strong screening properties of bilayer graphene lead to qualitative differen...

Exfoliated oxidized graphene (OG) sheets, suspended in an aqueous solution, were deposited on freshly cleaved HOPG and studied by ambient AFM and UHV STM. The AFM images revealed oxidized graphene sheets with a lateral dimension of 5–10 lm. The oxidized graphene sheets exhibited different thicknesses and were found to conformally coat the HOPG substrate. Wrinkles and folds induced by the deposi...

Carbon fiber reinforced polymer (CFRP) composites possess many advantages for aircraft structures over conventional aluminum alloys: light weight, higher strengthand stiffness-to-weight ratio, and low life-cycle maintenance costs. However, the relatively low thermal and electrical conductivities of CFRP composites are deficient in providing structural safety under certain operational conditions...

We have studied the effect of the oxidation path and the mechanical energy input on the size of graphene oxide sheets derived from graphite oxide. The cross-planar oxidation of graphite from the (0002) plane results in periodic cracking of the uppermost graphene oxide layer, limiting its lateral dimension to less than 30 μm. We use an energy balance between the elastic strain energy associated ...

Functionalized and fully characterized graphene-based lubricant additives are potential 2D materials for energy-efficient tribological applications in machine elements, especially at macroscopic contacts. Two different reduced graphene oxide (rGO) derivatives, terminated by hydroxyl and epoxy-hydroxyl groups, were prepared and blended with two different molecular weights of polyethylene glycol ...