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

Abstract

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 (∼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.