Amorphous Bimetallic Nanowires with High-Performance Microwave Absorption: A Case for FeCo Nanowires

Abstract

Amorphous FeCo nanowires (NWs) with the average diameter of 120[Formula: see text]nm were successfully prepared with a magnetic-field-assisted (MFA) hydrothermal method. Rapid reaction time was adopted to obtain amorphous FeCo NWs, being checked by XRD and TEM. Tuning the stoichiometric ratio of Fe/Co content meets the optimal impedance matching under different absorption frequency, making both improved intensities and frequency ranges of microwave absorption. For example, under 3[Formula: see text]mm coating thickness, the reflection loss (RL) peaks of Fe3Co7, Fe5Co5 and Fe7Co3 NWs are [Formula: see text]25.88[Formula: see text]dB at 4[Formula: see text]GHz, [Formula: see text]19.06[Formula: see text]dB at 4.24[Formula: see text]GHz and [Formula: see text]21.98[Formula: see text]dB at 5.44[Formula: see text]GHz. The related efficient absorption bandwidths ([Formula: see text]10 dB) of Fe3Co7 NWs, Fe5Co5 NWs and Fe7Co3 NWs are 5.40[Formula: see text]GHz, 3.52[Formula: see text]GHz and 4.91[Formula: see text]GHz, respectively. It is ascribed to integrating enhanced dielectric/conductive losses, negligible damages from eddy current effect and good impedance matching for high-performance FeCo NWs absorbers. This work paves a new path on synthesizing bimetallic wire-like nanostructures for microwave absorption demands.

Amorphous FexCo1–x Wire-like Nanostructures Manufactured through Surfactant-Free Magnetic-Field-Induced Synthesis

“…Therefore, this nanostructure obtained by X. F. Zhang et al 44 should be considered as the Fe−Co/PVP composite rather than the pure bimetallic nanoalloy. The most recent use of the MFI approach is proposed by J. Shen et al 45 who managed to produce bimetallic iron−cobalt nanowires with various chemical compositions through the MFI hydro-thermal method. They performed the process at 80 °C using NaBH 4 as the reducing agent of aqueous solutions containing Fe 2+ and Co 2+ ions.…”

Evolution of Structural and Magnetic Properties of Fe-Co Wire-like Nanochains Caused by Annealing Atmosphere

“…This observation is related to their partial oxidation during thermal treatment. Finally, it is worth adding that the obtained results can be considered as an important source of information for the application of thermally-treated Fe-Co nanochains as magnetic and microwave absorbers [ 27 , 28 ] or in catalysis [ 29 , 30 ].…”

“…The obtained results are collected and comprehensively described in this work. Moreover, it is worth noting that they can be considered as an important source of information for the application of the thermally-treated iron-cobalt Wire-like nanochains in the magnetic and microwave absorbers [ 27 , 28 ] or catalysis [ 29 , 30 ].…”

Preparation and characterization of CNT films/silicone rubber composite with improved microwave absorption performance

“…In practical demands of EM wave absorbers, the bandwidth of RL<−10 dB (here be denoted as f E ) exhibits that the absorbers have the ability of assimilating 90 % incident electromagnetic wave in the appointed bandwidth. It is widely accepted that f E is one important index for evaluation of EM wave absorption, which is equal with the intensity index as the minimum reflection loss (RL min ) [5,7,[49][50][51]. Figure 10(a) presents frequency bandwidth and intensity of the three CNT/SR absorbers (0.5 CNT powders/SR, 2.5 CNT powders/ SR and 0.5 CNT films/SR) in RL curves at 1 mm coating thickness.…”