Three‐dimensional graphene/carbon nanotube electromagnetic shielding composite material based on melamine resin foam template

Abstract Electromagnetic shielding materials with good ductility, low density, and high shielding performance have excellent application prospects in communication and electronics, aerospace, and military industry. Lightweight three‐dimensional porous conductive foam composite with high electrical conductivity and electromagnetic shielding efficiency has been widely concerned in recent years. In this study, we prepared a special physically modified carbonized melamine foam (CMF) by synergistic modification with graphene (GNs) and multi‐walled carbon nanotubes (CNTs). The lightweight CMF composite with a Unique 3D pore structure has been constructed to achieve high efficiency in EMI shielding. Taking advantage of the synergistic effect of few‐layer nanosheets and CNTs in tailored microporous structure, 15 wt% GNs‐CNTs/CMF composite demonstrates low density of 0.03 g/cm 3 and high electrical conductivity of 34.0 S/m, resulting in a significant EMI shielding effectiveness as 3840 dB⋅cm 2 /g. The microporous architecture contributes to multiple reflection losses of electromagnetic waves by introducing multiple interfaces and also improves the construction of conductive paths to deliver outstanding shielding performance. This work illustrates reference significance for the potential application of lightweight EMI shielding materials with target functions.