Room temperature deprotonation engineering for large-scale preparation of MIL-88B-like for efficient electromagnetic wave absorption

Abstract

Metal-organic frameworks (MOFs)-derived electromagnetic functional materials are a hot research trend in the field of microwave absorption (MA). However, there is a lack of high-yield strategies to drive high-performance MOFs-derived MA absorbers out of the laboratory. Herein, we prepared MIL-88B-like using a simple room-temperature liquid-phase method with more than 75 times the yield of the solvothermal method. The obtained MOFs were pyrolyzed to form C/FeO/FeN_0.0324/Fe quaternary composite materials. Under suitable graphitizing conditions, the moderate conductivity of derivative material of M1 precursor carbonized at 700 °C (M1-700) not only meets the requirement of impedance matching but also provides high conduction loss. Meanwhile, the multiple polarization loss mechanisms from defect-induced polarization, dipole polarization, heterogeneous interfaces, and magnetic loss mechanism synergize with each other, resulting in an effective absorption bandwidth (EAB) of 6.71 GHz and a reflection loss (RL) value of −62.57 dB at 22.5 wt% filler, which is a 6-fold increase in the RL compared with that of the conventional MIL-88B-derived wave absorber. In conclusion, this work provides a feasible solution for practical absorbers and an excellent reference value for high MA performance materials for applications.