A Study of Nanosize Fe₃O₄ Deposited on Carbon Matrix

Nanosized crystalline Fe₃O₄ (with an average particle size of 16 nm) was successfully synthesized on a carbon matrix surface. The prepared sample was heat-treated in the temperature range 300 °C–750 °C to remove residual impurities and to obtain a final product with a 77:23 ratio between magnetite and the carbon support. The sample was subjected to physicochemical and electrochemical tests. The purity of the phase and the particles size was determined by X-ray diffraction analysis and confirmed by field emission scanning electron micrographs. The specific surface area of the sample measured by the B.E.T method was 120 m² g⁻¹. A series of electrochemical tests including EIS, CV and long-term constant current cycling have been performed. The obtained reversible capacity within 15 cycles was in the range 400–550 mA h · g⁻¹. The electrochemical behavior of the test sample and its possible practical use as an anode material in lithium secondary batteries are discussed.