2D materials tagged posts

When a crystal is just one atom thick, melting gets weird — and scientists have finally caught it on camera.
When materials become just one atom thick, melting no longer follows the familiar rules. Instead of jumping straight from solid to liquid, an unusual in-between state emerges, where atomic positions loosen like a liquid but still keep some solid-like order. Scientists at the University of Vienna have now captured this elusive “hexatic” phase in real time by filming an ultra-thin silver iodide crystal as it melted inside a protective graphene sandwich.

When ice t...

In a controlled environment, the fastest-growing orientation of graphene crystals overwhelms the others and gets “evolutionarily selected” into a single crystal, even on a polycrystalline substrate, without having to match the substrate’s orientation. An Oak Ridge National Laboratory-led team developed the novel method that produces large, monolayer single-crystal-like graphene films more than a foot long. Credit: Andy Sproles/Oak Ridge National Laboratory, US Dept. of Energy

A new method to produce large, monolayer single-crystal-like graphene films more than a foot long relies on harnessing a “survival of the fittest” competition among crystals...