Microwave absorption properties of spheres-assembled flake-like FeNi3 particles prepared by electrodeposition

Flake-like FeNi3 particles based on submicrometre spheres self-assembly were prepared by electrode-position method using cetyltrimethylammonium bromide (CTAB) as the morphology modifier. To explore the formation mechanism of the novel flaky structures, three different concentrations of CTAB were employed to electrodeposit FeNi3 particles in the experiment. Linear sweep voltammetry were conducted to measure cathodic polarization curves of the corresponding three solutions. The crystal structure, morphology and electromagnetic properties of corresponding three samples were characterized by X-ray diffraction, scanning electron microscopy, vibrating sample magnetometry, vector network analysis. The effects of CTAB on the morphologies and structures of the FeNi3 particles were investigated. When the concentration of CTAB is 1.0 g/L, the prepared sample exhibited the best microwave absorption properties as a consequence of better electromagnetic impedance matching. The effective absorption bandwidth (RL < -10 dB) increases with decreasing thickness, reaching 4.32 GHz (13.2-17.52 GHz) when the absorber thickness is only 1.3 mm. The minimum reflection loss (RL) reaches -50.42 dB at 3.44 GHz. The absorbent with thickness of 1.3-2.5 mm obtains RL values exceeding -10 dB over a wide frequency range of 4.40-17.52 GHz, which covers almost the whole C, X and Ku-band (4-18 GHz). The microwave absorption properties of as-prepared FeNi3 particles possess the advantage of broad absorption bandwidth especially at thin thickness. (C) 2020 Elsevier B.V. All rights reserved.