Two-step synthesis of self-assembled 3D graphene/shuttle-shaped zinc oxide (ZnO) nanocomposites for high-performance microwave absorption

A unique three-dimensional (3D) structure nanocomposites composed of 3D graphene and shuttleshaped ZnO nanoparticles (3DGZ) were fabricated via a novel and facile two-step synthetic method in a solution phase technique. The microwave absorption properties of 3DGZ nanocomposites with different ZnO proportions were investigated. Morphology analysis showed that the shuttle-shaped ZnO nanoparticles were uniformly scattered on and embedded into 3D graphene without any aggregation, which is favorable to enhance the interfacial polarization. The sample 3DGZ-2 displayed the most outstanding microwave absorption performance. A minimum reflection loss of - 48.05 dB was obtained at 11.71 GHz with a thickness of 1.82 mm, and the RL exceeding - 10 dB were acquired in the frequency range covering from 12.98 to 17.06 GHz at a given thickness of 1.5 mm. Considering the outstanding performance of 3DGZ nanocomposites, we believe it has great potential to be used as a highly effective, lightweight, excellent heat stable and tunable microwave absorber. (C) 2019 Elsevier B.V. All rights reserved.