Core-Shell Chain-Like Cu@Ni Composite with Dual Absorption Peaks to Improve Microwave Absorption Properties

摘要

Core-shell Cu@Ni chains were successfully synthesized through a mild hydrothermal reaction. The morphology, structure and microwave electromagnetic properties of the composite were then characterized by X-ray diffraction, energy-dispersive spectroscopy, scanning electron microscopy and vector network analysis. The formation mechanisms of the core-shell structure and one-dimensional chains were ascribed to the varying redox potentials of Cu and Ni ions and the magnetic dipole-dipole attraction. Furthermore, a minimal reflection loss (RL) of -20.7 dB was observed at 9.6 GHz with a thickness of 2.0 mm and the effective absorption (= 10 dB, 90% microwave attenuation) bandwidth can be adjusted between 5.2 GHz and 16.6 GHz for the thin absorber thickness of 2.0-4.0 mm. The novel core-shell chain-like Cu@Ni alloy can be used as a promising absorbing material because it shows numerous features such as thin thickness, strong absorption, low cost and lightweight.