Rehybridization of carbon on facets of detonation diamond nanocrystals and forming hydrosols of individual particles

It was revealed that sp3-sp2 rehybridization of carbon atoms on the facets of nanocrystalline paricles of detonation diamond under thermal treatment results in weakening the hardness of its primary agglomerates. That discloses a secret of the unusual high strength of industrial diamond agglomerates and allows obtaining hydrosol of individual diamond nanoparticles ranging of 4–5 nm. Details of sp3-sp2 rehybridization have been studied by number of complementary methods including TEM, AFM, XPS, Raman scattering, X-ray diffraction and dynamic light scattering. A model for complete explanation of the processes during the annealing and obtaining stable hydrosols of 4–5 nm DND particles with different ζ-potentials is suggested. The model reveals the new ways for obtaining nanodiamond sols in other solvents.