Chirality—or ‘handedness’—is a symmetry property crucial to fields as diverse as biology, chemistry and high-energy physics. In graphene, chiral symmetry emerges naturally as a consequence of the carbon honeycomb lattice. This symmetry can be broken by interactions that couple electrons with opposite momenta in graphene. Here we directly visualize the formation of Kekulé bond order, one such ph...

The outstanding electrical, mechanical and chemical properties of graphene make it attractive for applications in flexible electronics. However, efforts to make transparent conducting films from graphene have been hampered by the lack of efficient methods for the synthesis, transfer and doping of graphene at the scale and quality required for applications. Here, we report the roll-to-roll produ...

Various physical properties of epitaxial graphene grown on SiC(0001) are studied. First, the electronic transport in epitaxial bilayer graphene on SiC(0001) and quasi-free-standing bilayer graphene on SiC(0001) is investigated. The dependences of the resistance and the polarity of the Hall resistance at zero gate voltage on the top-gate voltage show that the carrier types are electron and hole,...

A theoretical study is presented on the scattering of graphene surface plasmons (GSPs) by defects in the graphene sheet they propagate in. These defects can be either natural (as domain boundaries, ripples, and cracks, among others) or induced by an external gate. The scattering is shown to be governed by an integral equation, derived from a plane wave expansion of the fields, which in general ...

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...

The large polymer particle residue generated during the transfer process of graphene grown by chemical vapour deposition is a critical issue that limits its use in large-area thin-film devices such as organic light-emitting diodes. The available lighting areas of the graphene-based organic light-emitting diodes reported so far are usually <1 cm2. Here we report a transfer method using rosin as ...

We present chemical vapor deposition (CVD) growth of a hybrid structure of aligned graphene nanoribbons (GNRs) supported by a single-layer graphene sheet. The step structure created on the epitaxial Co film is used to segregate arrays of aligned GNRs. Reflecting the highly ordered step structure of the Co catalyst, straight nanoribbons with high aspect ratio (>100) are formed. Analysis suggests...

The rolling up of a graphene sheet into a tube is a standard visualization tool for illustrating carbon nanotube (CNT) formation. However, the actual processes of rolling up graphene sheets into CNTs in laboratory syntheses have never been demonstrated. Here we report conformal growth of graphene by carbon self-assembly on single-wall and multi-wall CNTs using chemical vapor deposition (CVD) of...

Due to fascinating electronic properties and great potential in various applications, graphene has attracted great interest. Recently, much work have focused on the synthesis of different sizes and properties of graphene or graphene oxides (GOs), for example, graphene nanoribbons, nanosized graphene pieces, and nanosized triangular and hexagonal graphene sheets terminated by zigzag edges. Herei...

Many proposed applications of graphene require the ability to tune its electronic structure at the nanoscale. Although charge transfer and field-effect doping can be applied to manipulate charge carrier concentrations, using them to achieve nanoscale control remains a challenge. An alternative approach is 'self-doping', in which extended defects are introduced into the graphene lattice. The con...