Nitrogen-Doped Hollow Carbon Microcubes Modified by in-Situ Catalytic Growth CNTs for Broadband Microwave Absorption

Abstract

3D hollow structural design and component regulation have been considered to bean effective strategy to obtain lightweight and wideband microwave absorption materials. Herein, nitrogen-doped hollow carbon microcubes modified by in-situ catalytic growth CNTs (Ni@CNTs/N-HCMs) were successfully fabricated by salt-template technique followed subsequent chemical catalyzed self-deposition (CCSD) and template removal process by simple water-washing. Benefiting from the unique structural merits improving the impedance matching and the synergistic effect of its components enhancing lossy capacity, the microwave absorption performance of the as-obtained Ni@CNTs/N-HCMs composites could be effectively regulated and optimized. The optimal reflection loss and the maximum effective absorption bandwidth can reach up to -46.7 dB at 3.7 mm and 6.1 GHz at 2.0 mm with the filling loading of only 3.5 wt%, respectively. Importantly, the salt templates are more economical and environmentally friendly, and can be recycled, which helps to prepare the product in large quantities. This study provides an innovative path to construct high-performance functional carbon-based absorption materials.