Preparation of N-Doped Graphene Oxide/Cobalt Nickelate Composites with Excellent Electromagnetic Wave Absorption

Abstract

The materials obtained by hybridization of different types of materials are widely used in the field of microwave absorption today. In this study, NRGO/CoNiO2 composites were effectively produced using a simple two-step technique. The structural study revealed a painstakingly constructed entanglement architecture made up of crumpled NRGO and CoNiO2 microspheres inside the NRGO/CoNiO2 composites as it was manufactured. NRGO/CoNiO2 composites have excellent microwave absorption properties, with an effective absorption of less (RL) than -10 dB at all thicknesses tested. The effective absorption bandwidth of 2.10 mm thick NRGO/CoNiO2 composite (40 wt.%) was 5.7 GHz, spanning from 12.30 GHz to 18.00 GHz. The optimal RL at a frequency of 10.6 GHz was notably improved to -52.1 dB at the thickness of 2.73 mm. This remarkable capability of absorbing microwaves is mainly associated with the joint effects of interfacial polarization, natural resonance, and the capacitor effect exhibited by NRGO and CoNiO2. The results show that NRGO/CoNiO2 composites can be used as efficient electromagnetic wave absorbing materials.

Keywords: Nitrogen doping, Reduced graphene oxide, cobalt nickelate, Composites, microwave absorption