▎ 摘　　要

A three-dimensional graphene/SiBCN hybrid composite was prepared by mixing and annealing Polyborosilazanes and sugar at 1200 degrees C. In this regard, the interface between the ceramic and the graphene formed a stable chemical bonding such as C-B-N, not physically absorbed as traditional meaning. Compared with the purity SiBCN ceramic, the hybrid material possessed a significant improvement on electromagnetic wave (EMW) absorption properties. When the thickness of the hybrid composites fixed on 2.5 mm, the maximum reflection coefficient (RC) increased from 1.36 to 24.24 dB and the bandwidth over 10 dB increased from 0 to 5.2 GHz. In addition, the bandwidth over 10 dB covered the whole X band when the thickness reached 3 mm. In short, this simple method was deemed to be a useful technology to fabricate a unique structure with excellent EMW absorption properties.