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Indexed by:Journal Papers

Date of Publication:2020-02-01

Journal:JOURNAL OF ELECTRONIC MATERIALS

Included Journals:EI、SCIE

Volume:49

Issue:2

Page Number:1204-1214

ISSN No.:0361-5235

Key Words:Electrostatic force; CoC-rGO hybrids; EMW absorption

Abstract:A two-step method has been adopted to synthesize cobalt nanoclusters in carbon (CoC)-decorated reduced graphene oxide (rGO) from graphene oxide (GO) and ZIF-67 as an excellent stable electromagnetic wave (EMW) absorber. Firstly, the electrostatic force between GO and Co2+ gave rise to in situ growth of ZIF-67 on GO (ZIF-67-GO). Then CoC-rGO was obtained by calcination of ZIF-67-GO hybrids. The ligand is introduced as the nitrogen source to GO. The crystal structure, chemical composition, and magnetic properties of CoC-rGO were investigated by x-ray powder diffraction analysis, Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, x-ray photoelectron spectroscopy, and vibrating-sample magnetometry. The morphology was observed by scanning electron microscopy and transmission electron microscopy. By adjusting the ratio of GO to ZIF-67, the electromagnetic parameters of CoC-rGO can be optimized. It was found that the sample consisting of 10 wt.% CoC-rGO-2 in a paraffin matrix exhibited excellent EMW absorption performance, reaching a minimum reflection loss (RLmin) of -44.77 dB with thickness of 2.1 mm and an effective bandwidth (RL <= -10 dB) of up to 5.2 GHz at thickness of 1.8 mm. The results of this study open an effective and simple avenue for the design of EMW absorbers using metal-organic framework (MOF) and low-cost carbon materials.