Aspect Ratio Design and Heterostructure Construction of MoO2/NC Nanorods for Broadband Microwave Absorption

Abstract

The exploration of high-performance wave absorbing materials is particularly critical for solving electromagnetic pollution. Based on the designability and structural virtue of one-dimensional anisotropic structure, a succession of MoO2/N-doped carbon (MoO2/NC) heterogeneous nanorods with various aspect ratios have been synthesized by hydrothermal, chemical oxidation polymerization and calcination process. To investigate the effect of aspect ratio on the microwave attenuation capacity, these fabricated nanorods are compounded with polyvinylidene fluoride (PVDF) under different filler contents. It is concluded that the aspect ratio can effectively regulate the microwave absorption performance. Specifically, the MoO2/NC-1/PVDF composites acquire the RLmin value of −56.9 dB at 2.9 mm and the RLmin value (−44.2 dB) of MoO2/NC-2/PVDF composites appear at a thinner thickness of 1.8 mm under a filler loading of 15 wt%. With the increment of aspect ratio, the optimal effective absorption bandwidth (EAB) of MoO2/NC-3/PVDF composites extend up to 6.32 GHz at 2.0 mm within a filler content of only 10 wt%, covering the whole Ku band. Meanwhile, the radar cross section simulations of MoO2/NC/PVDF composites further verify their immense potential in practical application. This work demonstrates that the aspect ratio design is conducive to acquisition for regulable and broadband microwave absorption under low filler loading.