Heterostructure design of hydrangea-like Co2P/Ni2P@C multilayered hollow microspheres for high-efficiency microwave absorption

Structural design and elemental doping are research hotspots for the preparation of lightweight absorbers with high absorption performance and low filling ratio. Herein, a P-doped hydrangea-like layered composite (Co2P/Ni2P@C) encapsulated with Ni-LDH was successfully synthesized by solvothermal method followed by phosphorization. The defects generated by P doping and the generation of multilayered nonuniform interfaces enhance the dielectric loss induced by polarization. Simultaneously, the magnetic phosphides induce magnetic loss and modulate the dielectric properties of the carbon matrix to enhance the conductive loss. The multilayered hollow structure of this composite promotes the scattering and reflection of electromagnetic waves and optimizes the impedance characteristics. As a result, the multilayered hollow Co2P/Ni2P@C composite exhibits an optimum reflection loss value (RL) of –64.6 dB at 15.1 GHz with a thickness of 2 mm and a filler ratio of only 10 wt%. The radar cross-section (RCS) attenuation further demonstrates that the material can dissipate microwave energy in practical applications. Overall, this work provides an effective development strategy for the design of multilayered high-performance electromagnetic wave (EMW) absorbers doped with strongly polarized elements.