Controllable synthesis of nitrogen-doped porous Fe3C@C nanocomposites for efficient microwave absorption

Three-dimensional (3D) porous carbon-based materials are commonly considered to be a hopeful microwave absorbing materials owing to their lightweight and broadband absorption. However, the structure between dissipation mechanism is still not clear. Therefore, in this work, the nitrogen-doped porous Fe3C@C nanocomposites derived from Fe(NO3)3 center dot 9 H2O and polyvinyl pyrrolidone (PVP) were fabricated through preblowing followed by in situ carbonization method with various temperatures. The obtained material treated at 600 degrees C, which the content of N was 4.07 %, exhibits the most excellent microwave absorption (MA) property with the minimal reflection loss of - 63.1 dB at 5.0 GHz while the matching thickness is 4.6 mm. The MA performance of the composite is originated from the synergy of magnetic-dielectric loss and improved interfacial polarization. This research provides a way to prepare high-property MA absorbers. (c) 2023 Published by Elsevier B.V.

Automated summary

In this study, nitrogen-doped porous Fe3C@C nanocomposites were fabricated by the preblowing and in situ carbonization method using Fe(NO3)3·9H2O and polyvinyl pyrrolidone (PVP). The material treated at 600 degrees C, with a nitrogen content of 4.07%, exhibited excellent microwave absorption properties with a minimal reflection loss of - 63.1 dB at 5.0 GHz and a matching thickness of 4.6 mm. The microwave absorption performance was attributed to the synergy of magnetic-dielectric loss and improved interfacial polarization. This research provides a method for the preparation of high-performance microwave absorbing materials.