▎ 摘　　要

There has been a great challenge in developing highly efficient electromagnetic microwave absorbers with strong absorbility, wide effective absorbing bandwidth and lightweight to solve the increasingly severe electromagnetic pollution. Here, we unveil the great potential of highly ordered mesoporous carbon coated graphene composites in the application of microwave absorption. The ordered mesoporous carbon composites possess well-defined spherical mesopores that are uniformly distributed on graphene surfaces and with uniform diameters of similar to 20 nm (graphene@mesoporous carbon, abbreviated as G/MC). This renders the nanocomposites with high BET surface areas of up to 316 m(2) g(-1). Impressively, the G/MC nanosheets carbonized at 900 degrees C (G/MC-900) exhibit an outstanding microwave absorbility, with a maximum reflection loss (RL) of -66.1 dB and an exceptionally broad effective absorbing bandwidth (EAB) of 8.2 GHz (RL < -10 dB) at ultralow filler loading of only 5 wt%. This microwave absorbility is superior to that of most microwave absorbing materials that have been reported, making the 2D mesoporous carbon nanocomposites a strong candidate for microwave attenuating materials. (C) 2021 Published by Elsevier Ltd.