Researchers show how borophene, the 2D form of boron, can be grown to simplify its use for applications.

Materials theorist Boris Yakobson of Rice’s George R. Brown School of Engineering and his group suggest a method to synthesize borophene, the 2D version of boron, in a way that could make it easier to free up or manipulate.

According to the group’s paper in the American Chemical Society journal ACS Nano, that would involve growing the exotic material on hexagonal boron nitride (hBN), an insulator, rather than the more traditional metallic surfaces typically used in molecular beam epitaxy (MBE).

The weaker van der Waals forces between the growing borophene and relatively chemically inert hBN would make it easier to remove the material from the substrate to use in applications. It would also allow for simpler direct evaluation of borophene (without lifting it from the substrate) for its plasmonic and photonic — that is, light-handling — properties because there would be no metallic substrate to interfere. That would also aid experimentation on its electronic properties, which could be of interest to those who study superconductivity.

The Yakobson team, including lead author and graduate student Qiyuan Ruan and co-authors Luqing Wang, a Rice alumnus, and research scientist Ksenia Bets, calculated the atom-level energies of borophene and hBN. They found the step-and-plateau hBN substrate encouraged boron atoms floating in the MBE chamber to alight, nucleating growth.

Because hBN, like graphene, has a chicken wire-like hexagonal lattice, its atomic arrangement also allowed for edge-epitaxial growth of the new crystal forming on its surface. In epitaxy, growth of the new material is dictated to a degree by the lattice below. In this case, that growth happens instead on the plateau’s raised side.

Story Source: Materials provided by Rice University. Original written by Mike Williams. Note: Content may be edited for style and length.