Flat boron by the numbers

It would be a terrible thing if laboratories striving to grow graphene from carbon atoms kept winding up with big pesky diamonds.

''That would be trouble, cleaning out the diamonds so you could do some real work,'' said Rice University theoretical physicist Boris Yakobson, chuckling at the absurd image.

Yet something like that keeps happening to experimentalists working to grow two-dimensional boron. Boron atoms have a strong preference to clump into three-dimensional shapes rather than assemble into pristine single-atom sheets, like carbon does when it becomes graphene. And boron clumps aren't nearly as sparkly.

Yakobson and his Rice colleagues have made progress toward 2-D boron through theoretical work that suggests the most practical ways to make the material and put it to work. Earlier calculations by the group indicated 2-D born would conduct electricity better than graphene.

Through first-principle calculations of the interaction of boron atoms with various substrates, the team came up with several possible paths experimentalists may take toward 2-D boron. Yakobson feels the work may point the way toward other useful two-dimensional materials.

The Rice team's results appear this week in the journal Angewandte Chemie International Edition. Rice graduate student Yuanyue Liu and research scientist Evgeni Penev are co-authors of the paper.