Carbon nanotubes decorated NiCo/C composite anchored on graphene oxide as broadband microwave absorber

Abstract

Developing an efficient EM wave absorbing material that can absorb EM waves in wide frequency range is a significant challenge. Herein, we construct a three-dimensional (3D) composite consisting with 2D graphene oxide (GO), 1D carbon nanotubes (CNTs), and 0D NiCo nanoparticles that can absorb electromagnetic waves over a wide frequency range. The GO possesses a large specific surface area and layered structure, which provide significant advantages for the in-situ growth of NiCo-MOF rods, and it effectively alleviates the issue of GO stacking. After thermal treatment, the NiCo@C nanorods decorated with CNTs and anchored to the surface of GO nanosheets is obtained (NiCo@CNTs@GO). The continuous and interconnected structure between the different components enables significant optimization of electron transport channels, creates ample spatial gaps and sites for enhanced electromagnetic wave reflections and scattering, and facilitate multiple heterogeneous interfaces for increased polarization losses. As a result, this NiCo@CNTs@GO microwave absorber exhibits an absorption intensity of −56.2 dB and highest effective absorption bandwidth of 8.88 GHz. This work offers a novel strategy and method for the research of high-efficiency broadband electromagnetic wave absorbing materials, holding significant theoretical value for advancing the applications of microwave absorption materials.