There is a critical need to develop lightweight and mechanically reliable materials for electromagnetic interference (EMI) shielding applications in the harsh environment. In this study, we propose a low-density (∼2.2 g/cm3) reduced graphene oxide (rGO)/silica ceramic with multilayer rGO sheets parallelly aligned inside the silica matrix through a new intercalation strategy. The parallel rGO sheets lead to outstanding EMI shielding effectiveness values of 29-33 dB in the X-band, owing to the interlayer multiple reflections of the electromagnetic wave. Meanwhile, the parallel rGO sheets elevate the flexural strength by 110-130% and improve the fracture toughness by 100-130% compared with the monolithic silica by capturing and deflecting the propagating cracks. The nanolaminated structure constructed by the intercalation approach can effectively break the trade-off between mechanical properties and EMI shielding performances in the graphene/ceramic composites, thus opening up new opportunities in the lightweight and mechanically reliable EMI applications.
Keywords: electromagnetic interference shielding; graphene/ceramic composites; intercalation; laminated structure; mechanical properties.