Enhanced Electromagnetic Wave Absorption by Porous Composites of Co-Containing Zeolitic-Imidazolate Framework

Abstract The composites of porous Co 3 O 4 /MWCNTs and porous Co 3 O 4 /Co/RGO have been prepared by the wet chemical method and carbonization process. Due to well impedance matching characteristics, dielectric loss properties and highly porous structure Co 3 O 4 /Co/RGO composite displays extremely strong electromagnetic wave absorption with a maximum reflection loss of –54.2 dB at 13.14 GHz and the absorption bandwidth with the reflection loss exceeding –10 dB is 5.46 GHz (10.24–15.7 GHz) with the thickness of only 2.0 mm. Furthermore, the addition amount of the composite into paraffin matrix is merely 10 wt %, less than that of most EMW absorber reported previously. Therefore, Co 3 O 4 /Co/RGO composite can be used as a promising lightweight EMW absorbing material.