The proliferation of electronic devises has resulted in electromagnetic pollutions, damaging to both human health and proper functioning of electronics. Despite of developments of conventional electromagnetic interference (EMI) shielding materials such as metals, reflection-dominant EMI shielding mechanism, giving rise to secondary EM wave pollutions and their intrinsic drawbacks including high density, susceptibility to corrosion and non-flexibility restrain them to be promising candidates to mitigate the adverse effects of EM waves. While myriad absorption-dominant porous structures for EMI shielding materials have been extensively explored, little attention has so far been placed on the effect of cell morphology for enhanced EMI shielding effectiveness (SE).

Herein, a biomi...[ Read more ]

The proliferation of electronic devises has resulted in electromagnetic pollutions, damaging to both human health and proper functioning of electronics. Despite of developments of conventional electromagnetic interference (EMI) shielding materials such as metals, reflection-dominant EMI shielding mechanism, giving rise to secondary EM wave pollutions and their intrinsic drawbacks including high density, susceptibility to corrosion and non-flexibility restrain them to be promising candidates to mitigate the adverse effects of EM waves. While myriad absorption-dominant porous structures for EMI shielding materials have been extensively explored, little attention has so far been placed on the effect of cell morphology for enhanced EMI shielding effectiveness (SE).

Herein, a biomimetic auxetic multifunctional MXene-coated polyurethane foam (MX/APU) with a negative Poisson’s ratio for EMI shielding and impact attenuation is developed using a facile dip coating method. The MX/APU presents a superior EMI shielding effectiveness and specific shielding effectiveness of 76.2dB and 1203dBcm³g^-1 respectively, showing a 31.2% increase in EMI SE against is non-auxetic counterpart, owing to the higher specific surface area of auxetic structure. Taking advantages of the negative Poisson’s ratio of auxetic structure, MX/APU delivers multifunctional enhancement properties for impact attenuation capability, achieving 71.7% reduction in the maximum impact force against its pristine parent foam. This work highlights the possibility to improve the EMI SE of porous materials by using auxetic structures, providing a conceptually new approach to design lightweight EMI shielding materials with excellent impact attenuating capabilities.