In situ growth of 3D multi-interface Ni@carbon nanotube networks towards highly-efficient microwave absorption

Abstract

In this paper, 3D multi-interface carbon nanotube networks were in-situ constructed from carbon nitride (g-C 3 N 4 ) and nickel chloride as precursors. With the temperature increase, g-C 3 N 4 was continuously decomposed to the components containing C and N element, and these produced compounds reduced Ni 2+ into Ni nanoparticles at the same time. After that, these compounds were enriched and precipitated on the surface of Ni nanoparticles, resulting in formation of bamboo-like carbon nanotubes with Ni particles embedded on the top (Ni@CNTs). The obtained Ni@CNTs exhibited high electromagnetic absorption performance with the filler loading content of 3 wt% in paraffin. The minimum reflection loss of 0.2Ni@CNTs was dramatically enhanced to − 31.7 dB and the effective absorption bandwidth was 6 GHz. The excellent microwave absorption performance was attributed to multi-interface reflections, good impedance matching and synergistic effects of multiple loss mechanisms from the Ni@CNTs. This work provides a new method to prepare multi-interface bamboo-like CNTs, which exhibited potential applications in microwave absorption. • Multi-interface carbon nanotube networks were constructed from g-C 3 N 4. • Excellent absorption resulted from multiple reflections and polarization losses. • Reflection loss reached − 31.7 dB with the EAB of 6 GHz under 3 wt% loading.