Effect of Carbon Concentration on Changing the Morphology of Titanium Carbide Nanoparticles from Cubic to Cuboctahedron

Abstract

Titanium carbide nanoparticles were synthesized by flowing methane through a plasma generated from an arc discharge between two titanium electrodes. Different methane concentrations were employed in studies made to investigate the effects of carbon concentration on particle morphology. Transmission electron microscopy and X-ray diffraction were used to investigate the synthesized TiC nanopowders, whereupon it was found that nanocrystalline TiC nanoparticles prefer a cubic morphology at low concentrations of methane and a cuboctahedron morphology at high concentration of methane. The change in particle morphology is attributed to carbon affecting the relative growth rates of the {111} and {100} facets on a TiC seed crystal.

The stability of TiC surfaces in the environment with various carbon chemical potential and surface defects

“…[22] In addition, carbon concentration was found to affect the morphology of the titanium carbide nanoparticles, e.g., cubic morphology is dominant at lower concentration of methane, while at higher concentration, cuboctahedron is dominant. [23] Hence, the investigation on surface energy in various environments is of great importance. On the other hand, the TiC is usually found to contain a lot of carbon vacancies.…”

“…With the increase of carbon chemical potential, the surface energy of the (001) surface becomes lower than that of Ti-terminated (111), suggesting that the (001) surface is more stable than the Ti-terminated (111) surface at the range of -1.54 eV ≤ ∆μ C ≤ 0 eV, where the (001) surface becomes the most stable surface and the order of stability is changed to: (001) >Ti-terminated (111) > (110) > C-terminated (111). The variation of the relative stability with carbon chemical potential will have an effect on the morphology of TiC nanoparticles and its chemical properties [23]. …”

A generic bamboo-based carbothermal method for preparing carbide (SiC, B4C, TiC, TaC, NbC, TixNb1−xC, and TaxNb1−xC) nanowires

“…[2][3][4][5][6][7][8] The combination of these superior properties gives rise to numerous applications, especially under extreme conditions, for example, light weight armors, abrasive wearresistant materials, high temperature resistant composites, high speed cutting tools, and high temperature microelectronics.…”

Substrate-mediated growth of vanadium carbide with controllable structure as high performance electrocatalysts for dye-sensitized solar cells

“…[27][28][29][30][31][32][33] Nevertheless, the synthesis of VC particles with well-dened morphology is rarely reported. [34][35][36] Traditionally, VC particles are synthesized by directly thermally annealing transitional metal oxides or metal salts with carbon containing precursors. 37,38 Unfortunately, the morphology is difficult to control and the particle size is mainly in micrometer scale for VC synthesized with such method.…”