Insights into the lanthanum doping large-size graphene oxide effect on the polymer composites

Despite the significant progress made in polymer/graphene nanocomposites, the development of high-performance polymer/graphene nanocomposites, combined with excellent mechanical and electromagnetic shielding properties, remains a priority and a challenge. The lanthanum doping large-size graphene oxide (La-LsG) was obtained via static oxidation and thermal treatment. The effects of static oxidation and lanthanum doping on the property and morphologies of graphene and composites were investigated. The physicochemical property of considerable graphene oxide (GO), large-size graphene oxide (LsGO), lanthanum-doped graphene oxide (La-GO), La-LsG was analyzed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, and X-ray energy spectroscopy (EDS). SEM and EDS characterized the microstructure of the composite material, and the mechanical properties and electromagnetic shielding performance of the composite material were studied. La-GO and La-LsG exhibited good dispersion and structural integrity, as well as enhancing the strength of the composites. The La-LsG/poly (methyl methacrylate) (PMMA) composites exhibited excellent mechanical properties (is ca. 73.6 MPa) and electromagnetic shielding effectiveness (is ca. 28 dB) in X-band frequencies (8.2–12.4 GHz), which may be assumed to be a promising integrated material of structure and function.