On the nature of simultaneous formation of nano- and micron-size diamond fractions under pressure–temperature-induced transformations of binary mixtures of hydrocarbon and fluorocarbon compounds

Abstract

Based on comparative studies of pressure–temperature-induced transformations of naphthalene, octafluoronaphthalene, and their binary mixtures, the nature of formation of nano- and micron-size diamond fractions in the products of transformations of hydrocarbons and fluorocarbons has been revealed. It was found that the main reason for the massive formation of nano-size diamonds is the specifics of carbonization of fluorocarbon compounds under pressure. In this particular process, micron-size particles of graphite are formed simultaneously with a significant amount of closed two- to five-layered carbon nanoparticles of 5–15-nm size, acting as precursors for the formation of nano-size diamond fractions. The obtained results open up a new avenue for the metal catalyst-free synthesis of nano/micron-size fractions of pure and doped diamonds.