MOF-derived multi-interface carbon-based composites with enhanced polarization loss and efficient microwave absorption

Metal-organic framework materials (MOFs) have been widely studied because of their adjustable composition and controllable structure in the field of microwave absorption (MA). Therein, Prussian blue analogs (PBA) have attracted the attention of researchers with ultra-high metal content. However, the attenuation ability of microwave for PBA-based composites is still unsatisfactory up to now. Therefore, the NiFe/CoFe@C composites were prepared by carbonizing polymetallic PBA (NiCoFe PBA) materials in this work, and the influence of different metal alloy components on MA was explored by adjusting the ratio of metal ions (Ni²⁺/Co²⁺). Moreover, the NiFe/CoFe@C composites have rich interfaces and enhance the polarization loss due to the introduction of Ni and it has an optimal performance at 2.7 mm that is the reflection loss (RL) is −41.49 dB and an effective absorption bandwidth (EAB) is 7.12 GHz with 1/1 (Ni²⁺/Co²⁺). The above data provides a research idea for obtaining light and efficient absorbers.