Exploiting the emulsification properties of low cost, environmentally safe Gum Arabic we demonstrate a high yield process to produce a few layer graphene with a low defect ratio, maintaining the pristine graphite structure. In addition, we demonstrate the need for and efficacy of an acid hydrolysis treatment to remove the polymer residues to produce 100% pure graphene. The scalable process give...

Grain boundaries (GBs) in graphene prepared by chemical vapor deposition (CVD) greatly degrade the electrical and mechanical properties of graphene and thus hinder the applications of graphene in electronic devices. The seamless stitching of graphene flakes can avoid GBs, wherein the identical orientation of graphene domain is required. In this letter, the graphene orientation on one of the mos...

Revealing the graphene growth mechanism at the atomic-scale is of great importance for achieving high quality graphene. However, the lack of direct experimental observation and density functional theory (DFT) verification hinders a comprehensive understanding of the structure of the carbon clusters and evolution of the graphene growth on surface. Here, we report an in-situ low-temperature scann...

Following a brief review of the device-friendly features of graphene, recent work on its Green's functions with and without a normal magnetic field are discussed, for an infinite graphene sheet and also for a quantum dot, with analyses of the Landau-quantized energy spectra of the sheet and dot. The random phase approximation dielectric response of graphene is reviewed and discussed in connecti...

We demonstrate the fabrication of a graphene/ZnO nanorod (NR) hybrid structure by mechanical exfoliation of ZnO NRs grown on a graphite substrate. We confirmed the existence of graphene sheets on the hybrid structure by analyzing the Raman spectra and current-voltage (I-V) characteristics. The Raman spectra of the exfoliated graphene/ZnO NR hybrid structure show G and 2D band peaks that are shi...

Graphene has been a subject of intense interest because of its unique physical properties. Raman spectroscopy became a valuable tool for determining the number of graphene layers and assessing their quality. Here we review our recent results on the effects of substrates and temperatures on Raman signatures of graphene. Specifically, we considered graphene on GaAs, glass, sapphire, standard Si/S...

We demonstrate the graphene assisted catalyst free growth of ZnO nanowires (NWs) on chemical vapor deposited (CVD) and chemically processed graphene buffer layers at a relatively low growth temperature (580 °C) in the presence and absence of ZnO seed layers. In the case of CVD graphene covered with rapid thermal annealed ZnO buffer layer, the growth of vertically aligned ZnO NWs takes place, wh...

The fabrication of graphene devices can be challenging due to exposure to harsh chemicals and mechanical wear such as ultrasonication used for cleaning in photolithography and metal deposition. Common graphene processing methods often damage fragile graphene sheets and can ruin the device during fabrication. The authors report a facile method to overcome many of these challenges, which is speci...

Graphene oxide was functionalized with simultaneous reduction to produce phosphonated reduced graphene oxide in a novel, fully scalable, one-pot method. The phosphonic derivative of graphene was obtained through the reaction of graphene oxide with phosphorus trichloride in water. The newly synthesized reduced graphene oxide derivative was fully characterized by using spectroscopic methods along...

We report a high-performance graphene/Si field-effect transistor fabricated via rapid chemical vapor deposition. Oligolayered graphene with a large uniform surface acts as the local gate of the graphene transistors. The scaled transconductance, gm, of the graphene transistors exceeds 3 mS/μm, and the ratio of the current switch, Ion/Ioff, is up to 100. Moreover, the output properties of the gra...