Shock-tube study of the formation of iron, carbon, and iron–carbon binary nanoparticles: experiment and detailed kinetic simulations

An experimental and computational study of the formation of pure iron nanoparticles, carbon nanoparticles (soot), and binary carbon-coated iron nanoparticles during the pyrolysis of iron pentacarbonyl–argon, ethylene–argon, and iron pentacarbonyl–ethylene–argon mixtures, respectively, behind reflected shock waves is carried out. The shape and size distribution of these nanoparticles are examined on a Zeiss Ultra plus ultrahigh-resolution field-emission scanning electron microscope. The binary iron–carbon particles were also investigated by high-resolution transmission electron microscopy and high-angle annular dark-field imaging (HAADF STEM) on a FEI Osiris transmission electron microscope equipped with a Bruker SuperX detector. Detailed kinetic simulations of the formation of these three types of particles are performed, which predict the concentration, average size, and size distribution of particles.