Hierarchical composite foams possessing an electric network layer modified with MoS2by atomic layer deposition as high-performance and tunable absorbers

Abstract

The construction of three-dimensional (3D) electric network structures is playing a crucial role in improving the electromagnetic energy attenuation ability in the design and synthesis of efficient and tunable electromagnetic waves absorbers.Herein, an extraordinary carbonized melamine skeletons (CMS) @ knitted Ni/N-doped carbon nanotubes (NCNTs) structure (labeled CK), in which the hollow CMS wrapped with 3D electric network layer is constructed via the intertwining of in-situ grown NCNTs, has been rationally designed and successfully fabricated through the anchoring of nickel hydroxide and pyrolysis processes. Meanwhile, the efficient and tunable microwave absorption performance of the CMS @ knitted Ni/NCNTs @ MoS2 (CKM) is achieved by introducing MoS2 into the 3D electric network layer via atomic layer deposition. The optimal microwave absorption performance can be observed in involved absorbers with a filling ratio of only 3.97 %, whose minimum reflection loss reaches up to −96.13 dB at a thickness of 2.62 mm and maximum effective absorption bandwidth is 8.2 GHz at 3.2 mm. By manipulating the loads of MoS2, the coverage of X-band and Ku-band can be implemented with a 6.68 % filling load at an absorber thickness of 2.5 and 1.9 mm, respectively. The construction of the unique microstructure and regulation of MoS2 loads are demonstrated to be feasible pathways for the production of efficient and tunable electromagnetic waves absorbers in future.