Enhanced microwave absorption performance of light weight N-doped carbon nanoparticles

Microwave absorbents with specific morphology and structure have fundamental significance for tuning microwave absorption (MA). Herein, N-doped carbon sphere nanoparticles and hollow capsules were successfully fabricated via oxidative polymerization of dopamine in different mixed solutions, without any template preparation or etching process. Compared to solid particles, the microwave absorbents consisting of N-doped carbon with a hollow structure showed enormously enhanced MA performance, exhibiting a broad effective absorption bandwidth (from 12.7 GHz to 17.9 GHz) and a minimum reflection loss of -27.2 dB with a sample thickness of 2.0 mm. This work paves an attractive way for simple and eco-friendly preparation of advanced light weight microwave absorbents.