Highly efficient electromagnetic wave absorption Fe-MOF-rGO based composites with enhanced flame retardancy

Abstract

Ideal electromagnetic absorbing material should not only be light weight, broadband and high efficient, but also easily prepared and flame-retarding to satisfy the challenges from rapid development of electronic information technology. In present paper, a new type of electromagnetic absorbent (Fe-MOF-rGO) was prepared via a simple one-pot method to grow metal-organic framework (Fe-MOF) on the surface of in-situ reduced graphene oxide (rGO) by solvothermal method. When 25 wt% of Fe-MOF-rGO was incorporated into the paraffin matrix, the minimum reflection loss value (RL) reached to −43.6 dB at the thickness of 2 mm, and the effective absorption bandwidth (EAB) exceeded 5.0 GHz, which satisfied the goals of high efficiency, light weight and broadband. According the medium permittivity loss, magnetization loss and excellent resistance matching results, it was concluded that the conduction loss (excellent conductivity of rGO), magnetic loss (magnetic resonance of Fe nanoparticles) and interface polarization loss (heterostructure of two-dimensional rGO and three-dimensional Fe-MOF) of Fe-MOF-rGO jointly determined the electromagnetic absorbing performance. Moreover, the combustible behavior of Fe-MOF-rGO was also investigated. When 10 wt% of Fe-MOF-rGO was incorporated into the epoxy resin (EP), the heat release capacity (HRC) and peak heat release rate (PHRR) decreased by 42.1% and 42.3% respectively, which showed an excellent flame-retarding property. • A new type of electromagnetic absorbent was prepared via a simple one-pot method. • The absorbent was not only broadband and high efficient but also excellent flame retardancy. • The absorbing mechanism was conduction, magnetic and interface polarization loss.