MCC: Specific of preparation, correlation of the phase composition and electrodynamic properties

Abstract

Metal-carbon composites (MCC) were produced by the dissolving of the Fe, Co and Ce nitrates in phenol–formaldehyde resin with further pyrolysis (under heating up to 800 °C). Concentrations of the metal compositions in final MCC were 2, 7 and 15 wt%. Phase composition of the final MCC samples was determined using XRD and Mössbauer spectroscopy. It was established phase separation in metallic compounds under pyrolysis process due to chemical interaction with phenol–formaldehyde decomposition products. The main phases for composites were: Fe3O4 (for MCC-Fe); Co (for MCC-Co) and CeO2 (for MCC-Ce). Average crystal size for metal-based fillers was 28, 24–35 and 3.5 nm for Fe-; Co and Ce-based composites respectively. The electrodynamic properties of the MCCs in the Extremely High Frequency range (30–50 GHz) were studied as function of the filler concentration. The frequency dependences of the permittivity and permeability (real and imaginary parts) of the investigated composites were measured. The nature of the MCC electrodynamic properties was discussed in detail in terms of polarization losses.