Synthesis, characterization and electromagnetic performance of nanocomposites of graphene with α-LiFeO2 and β-LiFe5O8

Abstract

Face-centered cubic α-LiFeO₂ and spinel β-LiFe₅O₈ with uniform size and high dispersion have been successfully assembled on 2D graphene sheets via a facile one-pot strategy under different reaction conditions. The reduction of GO by this method is effective and comparable to conventional methods, which was confirmed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The structure of the products can be easily controlled by changing the solvent and reaction temperature. It was shown that the as-formed β-LiFe₅O₈ and α-LiFeO₂ nanocrystals with a diameter of ca. 5 nm and 7 nm, respectively, were densely and uniformly anchored on the graphene sheets, and as a result, the aggregation of the nanoparticles was effectively prevented. The investigation of the microwave absorbability reveals that the α-LiFeO₂–GN and β-LiFe₅O₈–GN nanocomposites exhibit excellent microwave absorbability, which is stronger than that of the corresponding α-LiFeO₂ and β-LiFe₅O₈ nanostructures, respectively.