Recycled facial tissue derived carbon fiber decorated with cobalt-nickel nanoparticles promotes electromagnetic wave absorption performance

Designing and preparing electromagnetic wave absorbing materials (EWAM) with the characteristic of lightweight, wide frequency response and thin matched thickness is urgent needs and still exist challenge. Herein, EWAM composites of cobalt-nickel nanoparticles and carbon fibers derived from recycled facial tissue (NCFT) was constructed via the solvent-heating and heat-treatment process, which promote waste recycling and obtain satisfactory electromagnetic wave (EMW) absorption properties. Cobalt-nickel nanoparticles were homogeneously dispersed in the prepared carbon fiber matrix, resulting in a composite material with highly efficient EMW absorption properties. Experimental results show that the prepared composites exhibit excellent EMW-absorbing properties in the 2–18 GHz band, and a minimum reflection loss (RL_min) of −40.22 dB and an effective absorption bandwidth (EAB) of 4.5 GHz are obtained with a matched thickness of 1.3 mm. Furthermore, effective absorption for the C-band can be achieved with a thickness of 3.5 mm by adjusting the absorber's thickness. Through the comprehensive analysis of the microstructure and electromagnetic properties of the composites, it is found that the introduction of cobalt-nickel nanoparticles significantly enhances the dielectric loss and magnetic loss, and improves the absorption efficiency of electromagnetic waves. Besides, the radar cross section (RCS) simulation results illustrate the dissipation capability of NCFT composites in practical application scenarios. This study demonstrates the potential of NCFT in electromagnetic interference protection, also emphasizes the feasibility of using waste resources to prepare high value-added functional materials, providing new ideas and methods for environmental protection and resource reuse.