We synthesized disk-shaped and nano-sized graphene (DSNG) though a novel ion-exchange methodology. This new methodology is achieved by constructing metal ion/ion-exchange resin framework. The morphology and size of the graphene can be modulated by changing the mass ratio of the carbon-containing resin to the cobalt-containing precursor. This is the first time to show that the DSNG formed on the...

Graphene oxide-templated polyaniline (GO-PAN) microsheets were prepared via oxidation polymerization of aniline with graphene oxide (GO) as template. By applying this approach, irregularly shaped GO-PAN microsheets were obtained which was revealed by scanning electron microscopy (SEM). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements demonstrated that the resulted G...

We investigate spin conductance in zigzag graphene nanoribbons and propose a spin injection method based only on graphene. Combining density functional theory with tight-binding transport calculations, we find that nanoribbons with asymmetrically shaped edges show a non-zero spin conductance and can be used for spin injection. Furthermore, nanoribbons with rough edges exhibit mesoscopic spin co...

Although fullerenes can be efficiently generated from graphite in high yield, the route to the formation of these symmetrical and aesthetically pleasing carbon cages from a flat graphene sheet remains a mystery. The most widely accepted mechanisms postulate that the graphene structure dissociates to very small clusters of carbon atoms such as C(2), which subsequently coalesce to form fullerene ...

Stimulated by recent advances in isolating graphene, the authors discovered that a quantum dot can be trapped in a Z-shaped graphene nanoribbon junction. The topological structure of the junction can completely confine electronic states. By varying the junction length, the authors can alter the spatial confinement and the number of discrete levels within the junction. In addition, a quantum dot...

The mechanisms determining the growth of high-quality monolayer and bilayer graphene on Cu using chemical vapor deposition (CVD) were investigated. It is shown that graphene growth on Cu is not only determined by the process parameters during growth, but also substantially influenced by the quality of Cu substrate and how the Cu substrate is pretreated. It is found that the micro-topography of ...

Mid-functionalized ABC triblock copolymers with a short central B block were synthesized via the RAFT process, and further used as well-defined V-shaped copolymers to graft onto graphene oxide by coupling reactions.

This study reports on a facile and economical method for the scalable synthesis of few-layered graphene sheets by the microwave-assisted functionalization. Herein, single-layered and few-layered graphene sheets were produced by dispersion and exfoliation of functionalized graphite in ethylene glycol. Thermal treatment was used to prepare pure graphene without functional groups, and the pure gra...

Radio-frequency application of graphene transistors is attracting much recent attention due to the high carrier mobility of graphene. The measured intrinsic cut-off frequency (f(T)) of graphene transistor generally increases with the reduced gate length (L(gate)) till L(gate) = 40 nm, and the maximum measured f(T) has reached 300 GHz. Using ab initio quantum transport simulation, we reveal fo...

Top-gated graphene transistors operating at high frequencies (gigahertz) have been fabricated and their characteristics analyzed. The measured intrinsic current gain shows an ideal 1/f frequency dependence, indicating a FET-like behavior for graphene transistors. The cutoff frequency f(T) is found to be proportional to the dc transconductance g(m) of the device, consistent with the relation f(T...