Rose-derived Porous Carbon and In Situ Fabrication of Cobalt/Nickel Nanoparticles Composites as High-Performance Electromagnetic Wave Absorber

Rose-derived porous carbon and Cobalt(Co)/Nickel(Ni) nanoparticles composite absorbers (RC/Co and RC/Ni) were synthesized adopting a simple impregnation method and one-step carbonization method. The special array structure on the surface of rose petals remains intact even after carbonization, and the wrinkles and porous structure inside serves to reduce the material’s density and increase the number of interfaces. Besides, the in Situ Fabricated Co and Ni magnetic nanoparticles were employed to introduce magnetic loss ability. At a matching thickness of 1.58 mm, RC/Co exhibits a minimum reflection loss (RL_min) of -47.89 dB at 13.60 GHz and an effective attenuation bandwidth (EABW) of 4.08 GHz, while RC/Ni achieves a RL_min value of -45.36 dB at 12.88 GHz and an EABW of 3.02 GHz at thickness of 1.56 mm. Due to the low-cost biomass materials and simple preparation methods, RC/Co and RC/Ni could serve as a model for synthesizing other high-performance absorbers due to their environmental friendliness, convenience of synthesis, and good electromagnetic wave (EMW) attenuation capability.