Explosive New Process Produces Graphene by the Gram

You say you need some graphene so you can invent the Next Big Thing, but you can’t be bothered with processes that yield a few measly milligrams of the precious stuff. Luckily for you there’s a new method for producing gram quantities of graphene. Perhaps unluckily, it requires building a controlled fuel-air bomb.

Graphene is all the rage today, promising to revolutionize everything from batteries to supercapacitors to semiconductors. A molecularly-2D surface with unique properties, graphene can be made in very small quantities with such tedious methods as pulling flakes of the stuff off graphite lumps with Scotch tape. Slightly …read more

Continue reading Explosive New Process Produces Graphene by the Gram

One of the World’s Strongest Materials Looks Like a Chunk of Coral

It’s made of 3D printed graphene, the ultra-strong and lightweight carbon nanomaterial. And it could be great for building stuff in space. Continue reading One of the World’s Strongest Materials Looks Like a Chunk of Coral

Flexible, Sensitive Sensors from Silly Putty and Graphene

Everyone’s favorite viscoelastic non-Newtonian fluid has a new use, besides bouncing, stretching, and getting caught in your kid’s hair. Yes, it’s Silly Putty, and when mixed with graphene it turns out to make a dandy force sensor.

To be clear, [Jonathan Coleman] and his colleagues at Trinity College in Dublin aren’t buying the familiar plastic eggs from the local toy store for their experiments. They’re making they’re own silicone polymers, but their methods (listed in this paywalled article from the journal Science) are actually easy to replicate. They just mix silicone oil, or polydimethylsiloxane (PDMS), with boric acid, and apply …read more

Continue reading Flexible, Sensitive Sensors from Silly Putty and Graphene

Graphene Refractions

Researchers recently observed negative refraction of electrons in graphene PN junctions. The creation of PN junctions in graphene is quite interesting, itself. Negative refraction isn’t a new idea. It was first proposed in 1968 and occurs when a wave bends–or refracts–the opposite way at an interface compared to what you would usually expect. In optics, for example, this can allow for refocusing divergent waves and has been the basis for some proposed invisibility cloaking devices.

In theory, negative refraction for electrons should be easy to observe at PN junctions, but in practice, the band gap voltage causes most electrons to …read more

Continue reading Graphene Refractions

Making Graphene More Practical

[James Tour] and others at Rice University announced an improved form of graphene that uses nanoscale rivets. The material incorporates carbon nanotubes along with carbon spheres that encase iron nanoparticles. The nanotubes provide strength and higher conductivity overall, while the spheres let the material transfer more easily.

Typically, placing graphene on something involves using chemical vapor deposition on a polymer layer before transferring to another site. The polymer tends to degrade the graphene’s properties. This new material doesn’t require this intermediate step. In addition, the spheres allow interfacing to the graphene more readily.

The new material is almost as transparent …read more

Continue reading Making Graphene More Practical

Graphene Optical Boom Emits Light with No Diode

When a supersonic aircraft goes faster than the speed of sound, it produces a shockwave or sonic boom. MIT researchers have found a similar optical effect in graphene that causes an optical boom and could provide a new way to convert electricity into light.

The light emission occurs due to two odd properties of graphene: first, light gets trapped on the surface of graphene, effectively slowing it down. In addition, electrons pass through at very high speeds. Interestingly, the speeds are nearly the same–that is, electrons and trapped light travel at almost the same speed. The researchers found a way …read more

Continue reading Graphene Optical Boom Emits Light with No Diode