Urchin -shaped NiO/Ni particles with a heterojunction deposited on porous carbon via electroplating and low-temperature heat treatment for efficient microwave absorption

The incorporation of magnetic metals into carbon-based materials provides an effective approach to address the impedance matching imbalance inherent in pure carbon-based wave-absorbing materials. However, the challenge was found in developing simple and efficient methods to fabricate carbon-based composites. Herein, Ni particles with an urchin-like morphology to effectively attenuate electromagnetic waves were loaded on porous carbon derived from canola straw (hereafter referred to as CCS) via electroplating. Thereafter, urchin-shaped NiO/Ni particles with heterojunctions on the CCS (NiO/Ni@CCS) were constructed by a brief low-temperature heat treatment. Experimental and simulation results indicated that the heterogeneous interface caused interface charge redistribution, thereby enhancing conductive and dielectric losses. NiO/Ni@CCS performed an excellent microwave absorbability with a minimum reflection loss of −52.09 dB and a wider efficient absorption bandwidth of 5.1 GHz. The radar cross-section (RCS) simulation further confirmed that NiO/Ni@CCS exhibited superior microwave attenuation capability with an RCS reduction of 29.16 dB m². Moreover, NiO/Ni@CCS composite showed excellent corrosion resistance with a corrosion potential of −0.074 V for potential application in complex environments.