Multifunctional molecular precursor with tunable nano-microarchitecture enables exceptional electromagnetic waves absorption

Multi-component carbon is a promising candidate for electromagnetic wave (EMW) absorption materials. However, complex and non-green preparation process with low atomic utilization efficiency compromises the merits of carbon materials. Additionally, enhancing the electromagnetic wave absorption (EMWA) is highly desirable. To face the challenge, a multifunctional molecular precursor (DQSDCI) has been developed, characterized by high atom utilization efficiency (high char yield), abundant in-situ nitrogen doping, multi-sites for composite of nano-materials (e.g. CNT) or metal ion (e.g. iron) and green preparation (water solubility). The multi-component carbons derived from DQSDCI, featuring adjustable nanostructures (nanoribbons or nanosheets) and modifiable porosity, demonstrate outstanding EMWA. The multicomponent carbon of DQSDCI, iron and CNT (DQSDCI-Fe-CNT-700) demonstrated a minimum reflection loss (RL_min) of −69.57 dB and a maximum effective absorption bandwidth (EAB_max) of 5.7 GHz at about 2 mm thickness, covering a wide frequency range (4–18 GHz) by controlling the thickness between 1 and 5 mm. Moreover, simulation results indicated that the derived nanosheet is very promising application for aircraft stealth in a monostatic radar system. Abundant in-situ N doping, uniform distribution of MWCNT and ferromagnetic nanoparticles, hierarchical pore structures and various heterogeneous interfaces can synergistically improve the EMW attenuation ability by forming optimal impedance matching and multi-polarization loss.