Synthesis of Microporous Mo2C-W2C Binary Carbides by Thermal Decomposition of Molybdenum-Tungsten Blues.

Molybdenum and tungsten carbides are perspective catalytic systems. Their activity in many reactions is comparable to the activity of platinum group metals. The development of the synthesis method for of highly dispersed binary molybdenum and tungsten carbides is an important task. Dispersions of molybdenum-tungsten blue were used as a precursor for synthesis of binary molybdenum and tungsten carbides. The synthesis of carbides was carried out by thermal decomposition of molybdenum-tungsten blue xerogels in an inert atmosphere. The binary carbides were characterized by XRD, TGA, SEM and nitrogen adsorption. The influence of the molar ratio reducing agent/Me [R]/[ΣMe], molar ratio molybdenum/tungsten [Mo]/[W] on phase composition, and morphology and porous structure of binary carbides was investigated. Samples of binary molybdenum and tungsten carbides with a highly developed porous structure and a specific surface area were synthesized.

Synthesis of Mo2C by Thermal Decomposition of Molybdenum Blue Nanoparticles.

In recent years, the development of methods for the synthesis of Mo2C for catalytic application has become especially important. In this work a series of Mo2C samples was synthesized by thermal decomposition of molybdenum blue xerogels obtained using ascorbic acid. The influence of the molar ratio reducing agent/Mo [R]/[Mo] on morphology, phase composition and characteristics of the porous structure of Mo2C has been established. The developed synthesis method allows the synthesis to be carried out in an inert atmosphere and does not require a carburization step. The resulting molybdenum carbide has a mesoporous structure with a narrow pore size distribution and a predominant pore size of 4 nm.