We employ scanning probe microscopy to reveal atomic structures and nanoscale morphology of graphene-based electronic devices (i.e., a graphene sheet supported by an insulating silicon dioxide substrate) for the first time. Atomic resolution scanning tunneling microscopy images reveal the presence of a strong spatially dependent perturbation, which breaks the hexagonal lattice symmetry of the g...

An individual suspended graphene sheet was connected to a scanning tunneling microscopy probe inside a transmission electron microscope, and Joule heated to high temperatures. At high temperatures and under electron beam irradiation, the few-layer graphene sheets were removed layer-by-layer in the viewing area until a monolayer graphene was formed. The layer-by-layer peeling was initiated at va...

Solution-processable thin layer graphene is an intriguing nanomaterial with tremendous potential for electronic applications. In this work, we demonstrate that electrochemical exfoliation of graphite furnishes graphene sheets of high quality. The electrochemically exfoliated graphene (EG) contains a high yield (>80%) of one- to three-layer graphene flakes with high C/O ratio of 12.3 and low she...

Articles you may be interested in Terahertz, optical, and Raman signatures of monolayer graphene behavior in thermally reduced graphene oxide films J. Terahertz transmission and sheet conductivity of randomly stacked multi-layer graphene Appl. Optical investigation of reduced graphene oxide by spectroscopic ellipsometry and the band-gap tuning Appl.

We demonstrate electrical control over coherent optical absorption in a graphene-based Salisbury screen consisting of a single layer of graphene placed in close proximity to a gold back reflector. The screen was designed to enhance light absorption at a target wavelength of 3.2 μm by using a 600 nm-thick, nonabsorbing silica spacer layer. An ionic gel layer placed on top of the screen was used ...

The healing of graphene grown from a metallic substrate is investigated using tight-binding Monte Carlo simulations. At temperatures (ranging from 1000 to 2500 K), an isolated graphene sheet can anneal a large number of defects suggesting that their healings are thermally activated. We show that in the presence of a nickel substrate we obtain a perfect graphene layer. The nickel-carbon chemical...

Pauli blocking of interband transistions gives rise to tunable optical properties in single layer graphene (SLG). This effect is exploited in a graphene-nanoantenna hybrid device where Fano resonant plasmonic nanostructures are fabricated on top of a graphene sheet. The use of Fano resonant elements enhances the interaction of incident radiation with the graphene sheet and enables efficient ele...

Graphene and few-layer graphene at high bias expose a wealth of phenomena due to the high temperatures reached. With in-situ transmission electron microscopy (TEM) we observe directly how the current modifies the structure, and vice versa. In some samples, cracks propagate from the edges of the flakes, leading to the formation of narrow constrictions or to nanometer spaced gaps after breakdown....

Mechanically exfoliated graphene mounted on a SiO2/Si substrate was subjected to HF/H(2)O etching or irradiation by energetic protons. In both cases gas was released from the SiO2 and accumulated at the graphene/SiO2 interface resulting in the formation of "bubbles" in the graphene sheet. Formation of these "bubbles" demonstrates the robust nature of single layer graphene membranes, which are c...

Although graphene films have a strong potential to replace indium tin oxide anodes in organic light-emitting diodes (OLEDs), to date, the luminous efficiency of OLEDs with graphene anodes has been limited by a lack of efficient methods to improve the low work function and reduce the sheet resistance of graphene films to the levels required for electrodes1–4. Here, we fabricate flexible OLEDs by...