Abstract
A mechanism was established for the formation of nanosized iron carbide particles encapsulated in carbon shells via the processes of ferrocene thermal conversions at high pressures. At a pressure of 8.0 GPa, products of ferrocene decomposition were studied as a function of temperature by X-ray diffraction, Raman and Mössbauer spectroscopy, scanning and transmission electron microscopy. It was shown that the mechanism of formation of the carbon-encapsulated iron carbide nanoparticles at high pressures and temperatures differs qualitatively from the known mechanism of their formation in the gas-phase processes of laser pyrolysis or photolysis of ferrocene. At high pressures and temperatures, the formation of iron carbide nanoparticles occurs not due to the primary growth of pure iron particles and the subsequent dissolution of carbon in iron. Nanoparticles are formed due to the direct fusion of iron-carbon clusters, which are formed at intermediate stages of ferrocene thermal destruction. Then, obtained amorphous iron carbides Fe1- xC x with a high carbon content start to crystallize. Two crystalline carbon-encapsulated forms of iron carbide (Fe7C3 and Fe3C) are the main products of crystallization of the amorphous Fe1- xC x depending on the temperature of the ferrocene treatment.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.