The objective of this work is to synthesize pure stoichiometric titanium carbide and stoichiometric titanium carbide/hydride core-shell nanoparticles using the Guen-Miller Flow-Levitation method. The nanoparticulate are obtained via chemical reaction between nascent titanium nanoparticles and tailored gaseous hydrocarbons. Characterization of the nanoparticles is performed using analytical techniques including transmission electron microscopy, electron and X-ray diffraction, X-ray photoelectron spectroscopy, elemental analysis and specific surface area analysis. The results confirm the single-crystal nature and purity of the titanium carbide nanoparticles and demonstrate the coherence of single crystal titanium carbide core and titanium hydride shell in the TiC/TiH2 core-shell nanoparticles.
Abstract Nanopowders of titanium compounds TiH2 and TiC are synthesized via Flow-Levitation method using in situ reaction of nascent titanium nanoparticles with the proper reactants. The influence of manufacturing parameters on the composition and the internal structure of the synthesized nanoparticles is examined. Study of TiH2 nanoparticles using thermal methods revealed hydrogen evolution within the narrow temperature range (390-510°C), while hydrogen evolution temperature of the commercial samples is higher than 500°C.
Laboratory automated equipment for synthesis of ultrafine particles of metals, alloys and metal compounds via evaporation-condensation Flow-Levitation Guen-Miller method combined with crucible method using high-frequency (440 kHz) electromagnetic field for heating is described. The equipment synthesizes the said particles and multilayer core-shell structures with mean size ranging from tens to hundreds of nanometers with output from grams to tens of grams per hour. Synthesized particles may be collected into container with inert gas, or into non-volatile liquid, or in situ passivated with air for further handling. Examples of synthesized particles are presented.
Abstract Nanopowders of Fe-C system are synthesized via modified Guen-Miller Flow-Levitation method by in situ reaction of nascent iron nanoparticles with acetylene. Morphology, internal structure, chemical and phase composition are studied by electron microscopy methods, including electron diffraction and element analysis, X-ray phase analysis and CNHS chemical analysis. It is shown that depending on the parameters of the reaction with acetylene (temperature, concentration), particles composition can vary from pure iron with thin carbon coating complex composition consisting predominantly of iron carbide.
Комбинированная установка предназначена для получения ультрадисперсных (субмикронных и наноразмерных) порошков металлов, сплавов и соединений металлов, а также формирования на их основе «core-shell» структур с ядром из металла или соединения металла.