Carbon nanocages with N-doped carbon inner shell and Co/N-doped carbon outer shell as electromagnetic wave absorption materials

By Panbo Liu, Sai Gao, Yang Wang, Ying Huang, Wenjuan He, Wenhuan Huang, Juhua Luo. 2020

469 citations recorded by the source corpus.

Abstract Metal-organic-frameworks (MOFs)-derived carbon materials have been considered as promising candidates in electromagnetic wave absorption materials. However, precise design of MOFs-derived carbon materials with hollow structure still pose a formidable challenge. Herein, carbon nanocages have been synthesized by the direct pyrolysis of core-shell ZIF-8@ZIF-67 polyhedrons. Because of the different thermal stability of ZIF-8 core and ZIF-67 shell, the synthesized carbon nanocages are composed of N-doped carbon inner shell and Co/N-doped carbon outer shell. The micro-meso-macropores, enhanced conductive loss, strong dipolar/interfacial polarizations and core-shell Co@graphitic carbon layer favor the absorbers with high porosity, improved dielectric loss and promoted impedance matching. With a filler loading of 25 wt%, the maximum reflection loss reaches −52.5 dB at 13.1 GHz, and the effective absorption bandwidth exceeding −10 dB is 4.4 GHz (from 11.96 GHz to 15.36 GHz) with a thickness of only 2.2 mm. Furthermore, this work offers a simple and effective strategy in the fabrication of carbon nanocages with tuned chemical composition and improved impedance matching for lightweight and high-efficiency electromagnetic wave absorption materials.

Subfields: Electronic, Optical and Magnetic Materials

View Paper: https://www.semanticscholar.org/paper/9b8259b58e5b5a575471686e395951ea896e7faa