▎ 摘　　要

In order to simultaneously effective utilization of interface engineering, dielectric loss and magnetic loss attenuation mechanisms, we elaborately constructed and synthesized the mixed-dimensional magnetic nanoparticles (NPs)@carbon nanotubes (CNTs)-reduced graphene oxide (RGO) van der Waals heterostructures (VDWHs) through the catalytic decomposition of C2H2 over FeOOH-RGO. By controlling the decomposition time, different categories and CNTs contents of heterostructured nanohybrids such as Fe3O4@CNTs-RGO, Fe@Fe3C@CNTs-RGO and Fe@Fe2C@CNTs-RGO, which consisted of two-dimensional (2-D) RGO nanosheets, zero-dimensional (0-D) magnetic NPs and one-dimensional (1-D) CNTs, could be selectively synthesized. The obtained results indicated that the as-prepared mixed-dimensional magnetic NPs@CNTs-RGO VDWHs displayed the excellent microwave absorption capabilities, which were proved to be attributed to the quarter-wavelength matching model and good impedance matching. Moreover, because of the improved dielectric loss abilities, values of attenuation constant, defects and/or multiple interfacial polarizations, the obtained Fe@Fe2C@CNTs-RGO samples exhibited evidently enhanced microwave absorption performances. Therefore, a simple and effective route was proposed to synthesize the mixed-dimensional magnetic NPs@CNTs-RGO VDWHs, which provided a new platform for the designing and production of high performance microwave absorption materials. (C) 2019 Elsevier B.V. All rights reserved.