Facile Synthesis and Thermal Stability of Nanocrystalline Molybdenum Carbide

Abstract

Nanocrystalline molybdenum carbide (Mo<sub>2</sub>C) was prepared via one simple route by the reaction of metallic magnesium powders with molybdenum trioxide and potassium acetate in an autoclave at the condition of 600℃ and 4 h. X-ray powder diffraction (XRD) pattern indicated that the product was hexagonal α-Mo<sub>2</sub>C, and the cell constant was a = 3.0091 Å, c = 4.7368 Å. Scanning electron microscopy (SEM) image showed that the sample consisted of particles with an average size of about 100 nm in diameter. The product was also studied by the thermogravimetric analysis (TGA). It had good thermal stability and oxidation resistance below 450℃ in air

Thermal and structural studies of carbon coated Mo2C synthesized via in-situ single step reduction-carburization

“…2a ), which correspond to the sublimation of MoO 3 at higher temperatures (above 740 °C) as predicted by Chen et al . 43 . In this stage, decomposition of molybdenum oxide occurred in steps as observed from DTG (Fig.…”

“…Chen et al . 21 synthesized Mo 2 C at 600 °C using MoO 3 in an autoclave in presence of Mg and CH 3 COOK as reducing agent and carbon source, respectively. However, the authors did not establish the mechanism of reduction.…”

In situ single‐step reduction and silicidation of MoO3 to form MoSi2

“…In stage I, the oxidation of the MS8 sample occurs to form MoO 3 along with various other intermediate Mo‐based oxides (Mo 17 O 47 , Mo 4 O 11 , Mo 18 O 52 , Mo 8 O 23 , Mo 9 O 26 , MoO 2 ). Several researchers investigated the transformation of intermediate Mo‐based oxides to MoO 3 . They suggested that MoO 2 and MoO 3− x oxides form in the temperature range of 300‐600°C and the monoclinic MoO 3− x oxides transformed into the orthorhombic MoO 3− x oxides between 440 and 570°C.…”

Atmospheric chemical vapor deposition of graphene on molybdenum foil at different growth temperatures

“…Therefore, at higher growth temperatures, more carbon precipitates on the metal surface (sample 3). Consequently, the graphene layer on this sample is of superior quality compared to the other samples [24]. and increased the growth rate of graphene.…”

“…1, graphs 1, 2, and 3 show the XRD patterns of the Mo foils after deposition at different growth temperatures. The presence of Mo 2 C (carbide phase) peaks at 39.59° (101) and 52.31° (102) and the disappearance of Mo (110) indicate the presence of carbon atoms on the structure of the Mo foils as well as the precipitation of carbon onto the Mo surface [24]. The formation of carbide on the surface of Mo foils serves as an obstacle for the diffusion of more carbon onto the Mo surface; therefore, the deposited graphene is more uniform [18].…”