The growth mechanism of B/N co-doped diamonds under high pressure and high temperature

The B/N co-doped diamonds have been successfully fabricated in the graphitic mixtures of C and BN system with Fe–Ni alloy as catalyst under high pressure and high temperature conditions. Morphology and structural properties of the synthesized samples are characterized by optical microscope, scanning electron microscopy and X-ray diffraction. Raman spectrum and X-ray photoelectron spectroscopy are used to confirm their chemical composition and atomic-level hybrid qualities. Our results indicate that B, C and N combined with each other and formed stable chemical bonds in B/N co-doped diamonds, and the h-BN additive played an important role in determining the morphology of diamond crystal. The B/N co-doped diamond shows strip shape elongated along the {111} direction. According to our results, the possible growth mechanism is discussed.