Preparation and electromagnetic wave absorption of chain-like CoNi by a hydrothermal route

One-dimension CoNi chains with lengths of several to Lens and diameter of 1-2 mu m were synthesized through a tartrate assisted hydrothermal method at 140 degrees C for 15 h. The obtained CoNi chains were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TG). The electromagnetic characteristics of CoNi chains were studied at 1-18 GHz. The maximum reflection loss (RL) can reach -34.33 dB at 17.5 GHz with a thickness of 1.0 mm. The value of reflection loss below - 10 dB can be tuned in the 4.6-18 GHz by adjusting the absorber thickness of 1.0-3.0 mm. The excellent microwave absorption properties of the CoNi chains are ascribed to the good impedance matching, multiple polarization and unique chain-like shape. The experimental results showed that chain-like CoNi is a promising candidate as a low density, strong-absorption, wide-band and thin-thickness microwave absorber. (C) 2014 Elsevier B.V. All rights reserved.