Subangstrom edge relaxations probed by electron microscopy in hexagonal boron nitride.

Theoretical research on the two-dimensional crystal structure of hexagonal boron nitride (h-BN) has suggested that the physical properties of h-BN can be tailored for a wealth of applications by controlling the atomic structure of the membrane edges. Unexplored for h-BN, however, is the possibility that small additional edge-atom distortions could have electronic structure implications critically important to nanoengineering efforts. Here we demonstrate, using a combination of analytical scanning transmission electron microscopy and density functional theory, that covalent interlayer bonds form spontaneously at the edges of a h-BN bilayer, resulting in subangstrom distortions of the edge atomic structure.

Longitudinal splitting of boron nitride nanotubes for the facile synthesis of high quality boron nitride nanoribbons.

Boron nitride nanoribbons (BNNRs), the boron nitride structural equivalent of graphene nanoribbons (GNRs), are predicted to possess unique electronic and magnetic properties. We report the synthesis of BNNRs through the potassium-intercalation-induced longitudinal splitting of boron nitride nanotubes (BNNTs). This facile, scalable synthesis results in narrow (down to 20 nm), few sheet (typically 2-10), high crystallinity BNNRs with very uniform widths.

Plasmonic nanoparticle chains via a morphological, sphere-to-string transition.

Au nanoparticles encapsulated within polystyrene-block-poly(acrylic acid) (PS-b-PAA) micelles assemble into regular, one-dimensional arrays when they are exposed to solvent conditions that relax interfacial curvature in the micellar shell. Nanoparticle chaining was induced by adding salt, acid, or cationic carbodiimide to the suspension of purified encapsulated Au nanoparticles (Au@PS-b-PAA). The resulting assemblies were characterized by scanning and transmission electron microscopies, by dark-field optical microscopy, and by visible absorption spectroscopy.