Synthesis of Mo2c/C Nanoclusters Attached on Rgo Nanosheets for High-Efficiency Electromagnetic Wave Absorption

Abstract

It is an effective strategy that constructing composites with a multi-dimensional structure synergistically enhances the electromagnetic (EM) wave absorbing performance. Herein, a high-efficiency EM wave absorber of Mo2C/C nanoclusters uniformly and tightly encapsulated in rGO nanosheets (Mo2C/C-rGO) was prepared by a combination of the freeze-casting and subsequently carbothermal reaction method. Mo2C/C were in situ induced from spherical phosphomolybdic acid/polypyrrole (PMo12/PPy) to result in a unique cluster-like microstructure. Abundant heterogeneous interfaces in Mo2C/C-rGO composites endowed the excellent EM wave absorption performance at a low filling ratio of 5 wt%. The minimum reflection loss (RL) value was -49.3 dB at 1.38 mm and the maximum effective absorption bandwidth (EAB, RL<-10 dB) was 5.12 GHz at 1.60 mm. The excellent performance was owing to the Mo2C/C nanoclusters attached on rGO with lamellar structure and multi-heterogeneous interfaces, resulting in enhanced conduction loss and interfacial polarization, lengthening the transmission path of the incident wave. This universal strategy would be extended to other absorbers with multi-interface structures for lightweight and broadband EM wave absorption performance.

Keywords: Mo2C/C nanocluster-rGO composites, electromagnetic wave absorbing performance, freeze-casting