3D hierarchical Co₃O₄/Reduced graphene oxide/melamine derived carbon foam as a comprehensive microwave absorbing material

In this work, a simple and cost-effective method was developed to prepare a novel structure with Co₃O₄ nanoparticles dispersed on 3D graphene-wrapped carbon foam with melamine foam as initial skeleton. This Co₃O₄/Reduced graphene oxide/Melamine derived carbon foam (Co₃O₄/RGO/MDCF) hybrid with a continuous conductive network and low bulk density of 10.6 mg/cm³ exhibits high specific microwave absorption performance. The maximum Reflection Loss (RL) value of −31.88 dB at 11.54 GHz and a qualified bandwidth of 3.4 GHz (RL ≤ −10dB) with the coating layer thickness of only 2.0 mm under 10 wt% loading was achieved by Co₃O₄/RGO/MDCF composite. Notably our work provides a general and low-cost method to fabricate comprehensive microwave absorption materials with high RL value, low density, thin thickness and low loading content, which can be applied on scale and meet the requirement for the new type of electromagnetic wave absorptive material.