The shape and surface structure of detonation nanodiamond purified in oxidizing chemical environment

The structure of detonation nanodiamonds purified in the ozone, in a mixture of sulfuric acid with chromic anhydride and in nitric‑sulfuric acid in a presence of SO3 was examined. It is showed that in all cases oxidation leads to etching of (110) grain surfaces. The shape of as-synthesized nanograins evolves from initially truncated cube-octahedron with the same surface areas of (100), (110) and (111)A faces towards grains with increased area of (110) phase. The grains exposed to ozone become dodecahedrons terminated by (110) surfaces. [Display omitted] •Pair distribution function is used to identify nanodiamonds shape.•Real structure of nanodiamonds is modelled by molecular dynamics.•Purification in nitric-sulfuric acid mixture exposes (100), (110) and (111) faces.•Etching in chromic-sulfuric acid promotes formation of (110) faces.•Etching in ozone leads to formation of (110) dodecahedrons.