Formation of titanium-cobalt nitride Ti$_{0.7}$Co$_{0.3}$N under plasma-chemical synthesis conditions in a low-temperature nitrogen plasma

Nanocompositions with “core-shell” structure are of interest in different areas of materials science and solid state chemistry, since, along with traditional refractory components in the form of carbides or nitrides and individual metals (Ni, Co), phases of mixed composition of the type Me1$_{1-x}$Me2$_x$N (Me1–a refractory element of IV-VIA subgroup, Me2–Ni or Co) are formed during synthesis within one highly dispersed particle. It should be noted that such multicomponent phase components are metastable and cannot be obtained in an individual state. At the same time, phases of the Me1$_{1-x}$Me2$_x$N type are formed in systems with participation of nitride compounds during extreme processing. In the present work, the technology of plasma-chemical synthesis with subsequent recondensation of gaseous nitrogen in a rotating cylinder was used.
The work is aimed at obtaining metastable complex-substituted titanium-cobalt nitride Ti$_{0.7}$Co$_{0.3}$N in the framework of nano- and ultra-dispersed Ti(Mo)C–Co “core-shell” structures. All phase components of the claimed compositions were determined by X-ray diffraction. Additionally, Ti(Mo)C–Co nanoparticles were studied by high-resolution transmission electron microscopy and electron diffraction. It was determined that Ti$_{0.7}$Co$_{0.3}$N has a strongly deformed stressed state, as evidenced by a single reflection (101) on the X-ray diffraction pattern. The paper also considers some aspects of crystal chemical design of Ti$_{0.7}$Co$_{0.3}$N obtained in the course of structural and morphological certification of the Ti(Mo)C–Co nanocomposition.