The structure and electrochemical properties of fayalite Fe2SiO4

Abstract

Fayalite has been found various applications in many fields. Here is presented its use as anode material for lithium ion batteries. The syntheses of Fe2SiO4 and its composite with carbon are conducted through solid-state reaction at 850 °C under inert atmosphere of argon, using cheap and abundant precursors (Fe(NO3)3×9H2O and amorphous silica). Citric acid served as carbon source. The phase-purity of synthesized powders is checked by X-ray powder diffraction. The crystal structure of the powders is refined in orthorhombic Pbnm space group. Half-cell configuration, with lithium metal as counter electrode and fayalite as working electrode, is used for electrochemical measurements: galvanostatic cycling and electrochemical impedance spectroscopy.