▎ 摘　　要

FeNi3 nanocrystals as an ideal candidate for EM-wave-absorption material have a great advantage due to their excellent magnetic properties. However, its large permittivity and poor chemical stability confine its application. A strategy to improve electromagnetic performance of FeNi3 via phase-controlled synthesis of FeNi3 nanostructures grown on graphene networks has been employed in this work. The phases, structures, sizes and morphologies of FeNi3 nanocomposites were in-depth characterized by using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), powder X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), and Raman spectroscopy. The results of electromagnetic performance tests for the as-synthesized FeNi3 nanocomposites showed excellent microwave absorbability in comparison with the corresponding FeNi3 nanocrystals, especially in the low (2-6 GHz) and middle (6-12 GHz) frequencies. The one-pot method we utilized is simple and effective, and because of its versatility, it may be extended to prepare some magnetic metal or alloy materials via this route. (C) 2016 Elsevier B.V. All rights reserved.