Microwave absorption property of GO-Fe/FeO-NiO HNFs: GO decorated Fe/FeO-NiO hexagonal flakes with a 2D/0D/2D structure

In this study, Fe/FeO-NiO HNFs in which 2D NiO hexagonal nanoflakes (NiO HNFs) were decorated by 0D Fe/FeO NPs were prepared by a facile hydrothermal method. Then, 0D/2D Fe/FeO-NiO HNFs were loaded on 2D GO sheets in three different weight ratios of GO (1 : 3), (1 : 4), and (1 : 5) to Fe/FeO-NiO HNFs and a novel GO-Fe/FeO-NiO HNF composite with a 2D/0D/2D structure was successfully produced. TEM images revealed the interesting morphology of the GO-Fe/FeO-NiO HNF composite in which individual FeO NPs with a narrow size distribution (similar to 15 nm) were arranged in hexagonal NiO nanoflakes, decorated on the GO substrate. Since the morphology of nanomaterials has an important effect on their microwave absorption properties, designing a composite with an asymmetric morphology, which is the combination of zero, one, and two-dimensional nanostructures can be very efficient for adjusting the microwave absorption property. The microwave absorption ability of GO-Fe/FeO-NiO HNF composites was surveyed. All samples of Fe/FeO-NiO HNF composites exhibited superior microwave attenuation performance in terms of reflection loss with a suitable bandwidth. The minimum reflection losses for GO-Fe/FeO-NiO HNFs (1 : 3), (1 : 4), and (1 : 5) reached -75.22, -53, and -18 dB, respectively, and the effective absorption bandwidths (RL <= -10 dB) for GO-Fe/FeO-NiO HNFs (1 : 3), (1 : 4), and (1 : 5) were 2, 3 and 3.2 GHz, respectively.

Automated summary

Fe/FeO-NiO HNFs were prepared by decorating 2D NiO hexagonal nanoflakes with 0D Fe/FeO NPs using a hydrothermal method. The 0D/2D Fe/FeO-NiO HNFs were then loaded onto 2D GO sheets in different weight ratios, resulting in a novel GO-Fe/FeO-NiO HNF composite with a 2D/0D/2D structure. TEM images revealed the interesting morphology of the composite, with individual FeO NPs arranged in hexagonal NiO nanoflakes on the GO substrate.