Synthesizing a unique nanographene may advance spintronics applications

Graphene, despite its excellent mechanical, electronic and optical properties, is traditionally not deemed suitable for magnetic applications. Swiss Federal Laboratories for Materials Science and Technology (EMPA) Researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronics applications.

Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties. Together with colleagues from the Technical University in Dresden, Aalto University in Finland, Max Planck Institute for Polymer Research in Mainz and University of Bern, Empa researchers have succeeded in building a nanographene with magnetic properties that could be a decisive component for spin-based electronics functioning at room temperature.

Graphene enables researchers to visualize the flow of electrons

Researchers from Israel's Weizmann Institute and the UK's Manchester University have succeeded in imaging electrons' hydrodynamic flow pattern for the first time using a novel scanning probe technique. They have proven the longstanding scientific theory that electrons can behave like a viscous liquid as they travel through a conducting material, producing a spatial pattern that resembles water flowing through a pipe.

The results of this study could help developers of future electronic devices, especially those based on 2D materials like graphene in which electron hydrodynamics is important.

Skanska on its way to trial graphene-enhanced asphalt on the M25

Earlier this month, it was reported that Directa Plus and Skanska are getting ready a trial of re-surfacing a section of a UK road in Curbridge, Oxfordshire with materials containing G+ graphene substance. Now, Skanska has mentioned that it is also in talks to trial the graphene-enhanced asphalt on the UK's M25.

The Curbridge works, which were delivered by subcontractor Aggregate Industries, involved removal and reinstatement of the existing carriageway to a depth of 150mm over a 750m-long section. One lane was replaced using conventional materials, while the opposite ‘trial’ lane was resurfaced using the asphalt enhanced by the innovative asphalt modifier.

Magic-angle graphene reveals new phases

In 2018, researchers at MIT demonstrated superconductivity in magic-angle bilayer graphene. Now, Dmitri Efetov of the Institute of Photonic Sciences in Barcelona, Spain, and his colleagues have replicated MIT's results and discovered even more states in magic-angle graphene. By preparing a high-quality device, Efetov’s team could measure the electronic phases more accurately and resolve previously hidden electronic states.

To realize the magic angle, the researchers use an established technique: They take one sheet of graphene and tear it in two. They then rotate one of the pieces just past the magic angle, by about 1.2°, and stack it on top of the other. In most electrical devices, the final step is annealing to clean the sample and get rid of any air bubbles between the layers. But in magic-angle graphene, with the layers misaligned by such a small angle, heating the sample snaps the graphene layers back into alignment. Instead of annealing, Efetov and his colleagues rolled the top layer down gradually, starting from one edge, rather than dropping the second layer directly down onto the first. That method squeezes out any air bubbles as they form. The result is a relative angle that varies by only 0.02° over a 10 µm device, a record for magic-angle graphene. The fabrication overall is tricky; it was reported that in three months of trying, just 2 of the 30 devices worked.

Indian researchers make a discovery that may change existing graphene synthesis methods

A team of researchers at IIT-Gandhinagar in India has discovered an unexpected phenomenon that could have significant implications on the existing protocols followed to synthesize graphene and other two dimensional (2D) nanomaterials.

A popular method to synthesize graphene is liquid-phase exfoliation, in which the graphite powder is mixed in a suitable liquid medium and exposed to bursts of high-intensity sound energy (ultrasonication). This ultrasonic energy delaminates the layered parent crystals into daughter nanosheets that suspend and swim in the organic solvents to form a stable dispersion of 2D nanomaterials.

Versarien - Think you know graphene? Think again! Versarien - Think you know graphene? Think again!