Design of carbon aerogels with variable surface morphology for electromagnetic wave absorption

Carbon-based materials, as one of the most important electromagnetic wave absorbing materials, face the main problem of narrow effective absorption bandwidth. Here, carbon aerogels modified by carbon microspheres with different morphologies were prepared by controlling reaction parameters and carbonization process. The integral pouring method was proposed to test the electromagnetic parameters for the first time, which retained the skeleton structure of carbon aerogels. The complete skeleton and unique surface morphology significantly improve the electromagnetic wave absorption performance of carbon aerogels. At a low filling rate (7.7%), the effective absorption bandwidth is 8.47 GHz at 3.0 mm. The reflection loss absorption rate reaches 99.6%, meeting the requirements of efficient electromagnetic wave absorbing materials with wide bandwidth, thin thickness, and light weight.