Polycrystalline ZrN_1-xC_x Layers with (111) Preferred Orientation Prepared by the Carbothermal Nitridation of ZrO₂ Ceramics

Abstract

Polycrystalline ZrN 1-x C x layers have been prepared by the carbothermal nitridation of consolidated ZrO 2 ceramics. Thermodynamic analysis indicates that the formation of ZrN 1-x C x is favored by increasing the reaction temperature and the pressure of N 2 . The kinetics in the carbothermal nitridation is studied, and the overall reaction is considered to be controlled by the infiltration and diffusion of gaseous reactants. From the surface to the center, the sample shows a porosity gradient due to the difference in reaction degree. A strong (111) preferred orientation is observed in the as-synthesized ZrN 1-x C x layers, which is enhanced at elevated temperatures and higher pressures of N 2 . It is proposed that the growth of ZrN 1-x C x crystals takes place by the two-dimensional nucleation and growth mechanism.

Novel pseudo-morphotactic synthesis and characterization of tungsten nitride nanoplates

“…Recently TiN [4], CrN [5], GaN [6] and ZrN [7] have been intensively investigated in synthetic methods, structural characterization and applications. As one important member of metal nitrides, tungsten nitrides (W x N) have many promising properties, including good chemical stability, high strength, high hardness, high melting point with good electrical conductivity and a relative low band gap (2.2 eV) [8][9][10].…”