Synthesis and Study of Iron-Graphene Composites

Iron-graphene composites were synthesized by heat treatment of a mixture of iron (III) nitrate and graphite oxide in an argon flow, followed by reduction in a hydrogen flow. The composites were characterized by elemental analysis, thermogravimetry, scanning electron microscopy with energy-dispersive X-ray spectra and construction of maps of the spatial distribution of components, X-ray phase analysis, and Mossbauer spectroscopy. It was shown that the synthesized composites are sheets of a graphene-like material with iron-containing nanoparticles deposited on them, the size of which depends on the concentration of the iron compound in the original mixture. Iron nanoparticles in the obtained composites are rapidly oxidized upon short-term contact with air and can be restored by cyclic treatment at 400°C, including vacuuming the composite followed by exposure to hydrogen under pressure.