Will the next super materials be comprised of metallic ribbons of boron?
Researchers at Rice found one-dimensional forms of boron, including both single-atom chains and two-atom-wide ribbons, feature unique physical qualities. They described the qualities in the Journal of the American Chemical Society.
When stretched, the ribbons become antiferromagnetic semiconducting chains. During an antiferromagnetic moment, the spin rates of a material’s atoms form a uniform pattern, with neighboring spins aligning in opposite directions.
The combination of semiconducting and antiferromagnetic properties is appealing to spintronics researchers working to develop high-capacity electronic components and devices.
The only problem is metallic ribbons of boron and their properties only exist in theory. Materials scientists at Rice tested the unique boron forms using a sophisticated computer model.
Synthesizing new materials is expensive and time intensive, so it makes sense to model a material’s potential first.
“We wanted to know if it is stable and what the properties would be,” Rice researcher Boris Yakobson said in a news release. “That’s where modern theoretical-computational methods are impressive, because one can do pretty realistic assessments of non-existing structures.”
Researchers are currently working on making single-atom chains and two-atom-wide ribbons of metallic boron a reality.
“Even if they never exist, they’re still important since we’re probing the limits of possibility, sort of the final frontier,” Yakobson said.
Yakobson likes the structure of carbon chains, which form graphene, to the double-rowed truss of a bridge. Boron chains are more like a Slinky. They’re strong when resting in their natural state, but take on new properties when stretched. When released, they return to their original structure.
“If you pull on it, it starts unfolding; the atoms yield to this monatomic thread,” Yakobson explained. “And if you release the force, it folds back. That’s quite fun, structurally, and at the same time it changes the electronic properties.”
Filed Under: Materials • advanced