Maximized internal scattering in heterostack Ti3C2T x MXene/graphene oxide film for effective electromagnetic interference shielding

Abstract

Two-dimensional (2D) MXenes have attracted significant attention in electromagnetic interference (EMI) shielding applications due to their excellent metallic conductivity, high surface area, 2D geometry, tunable surface chemistry, and solution processability. In this study, we present a straightforward way of introducing multiple nanoscale interfaces into Ti3C2T x MXenes using insulating graphene oxide (GO) intercalants to enhance internal scattering, resulting in improved EMI shielding effectiveness (SE). The amine-functionalized MXene with positive surface charge and negatively charged GO flakes are electrostatically self-assembled to form a 2D/2D heterostack of MXene/GO nanosheets. The resultant 2D/2D alternating heterostack of MXene/GO bearing multiple internal interfaces with significant impedance mismatch enhances the internal scattering of incident electromagnetic (EM) waves. Interestingly, despite their inferior electrical conductivity, the MXene/GO heterostack films exhibit higher EMI SE values than the randomly mixed hybrid films, and even outperform pristine MXene films. These MXene/GO heterostack films with enhanced absorption of EM waves via the strong internal scattering effect suggest a valuable pathway toward practical EMI shielding with thin and lightweight features.