Ti₃C₂ MXenes meta-film switching ultra-broadband and high-efficiency green EMI shielding

Abstract

Green electromagnetic interference (EMI) shielding is embarking on a new direction to promote harmony with nature, especially in nowadays' booming big data, artificial intelligence, etc. However, the irreconcilable contradiction between strong electromagnetic attenuation and weak secondary reflection inevitably blocks its development. Herein, a new synergistic strategy of manipulating and attenuating the reflected wave is proposed for the first time in the field of EMI shielding, which successfully breaks through the bottleneck and realizes efficient and ultra-broadband green EMI shielding. The maximal EMI shielding effectiveness (SE) reaches up to ∼68.3 dB, and gs > 1 covers ∼10.4 GHz, enshrouding ∼65% of the investigated frequency range from 2 to 18 GHz. The bandwidth for gs > 10 even spans over ∼2.5 GHz. More importantly, it has great flexibility and robustness. The configured Ti3C2 MXenes-based meta-film can maintain good green EMI shielding ability regardless of being bent by the y-axis or x-axis torque. All these advantages arise from the synergistic effect between the phase manipulation of Ti3C2 MXenes-based Pancharatnam–Berry (PB) meta-atoms and the strong electromagnetic attenuation of Ti3C2 MXenes nanosheets take full advantage of the high conductivity and dipole polarization of Ti3C2 MXenes, leading to significant suppression of secondary reflection as implementing efficient EMI shielding. This finding provides a pathway to realize promising flexible, high-efficiency, ultra-broadband EMI shielding materials, or even dual-functional materials for electromagnetic shielding and absorption.