Centrifugal casting-enabled highly-oriented MXene-based layered films with dual-shielding against electromagnetic wave and infrared radiation

MXene-based layered films show great promise for electromagnetic interference (EMI) shielding, yet maintaining highly ordered structures during large-scale production remains challenging. Herein, we present a facile centrifugal casting method for scalable fabrication of MXene/polyvinyl alcohol (MXene/PVA) films with highly oriented and compact layered structures. During centrifugal casting, the viscous fluid experiences strong shear and centrifugal forces along the tangential and normal directions, respectively, inducing compact and oriented arrangement of MXene nanosheets in the layered structure. Consequently, the Herman’s orientation factor of MXene in composite films shows a significant increase from 0.681 to 0.794 as the rotation rate rises from 0 to 4000 r/min. Accordingly, the tensile strength and toughness of the composite film increase from 55.2 to 191.1 MPa, and from ~0.8 to 2.5 MJ/m3. More importantly, the highly oriented and compact layered structure with the ultrathin thickness (~8 μm) enables a high absolute electromagnetic shielding effectiveness (SSE/t) of 21029 dB cm2/g. Moreover, the increased oriented arrangement of MXene in the layered structure can significantly reduce the infrared emissivity to 0.248, thus endowing the MXene/PVA film with excellent thermal camouflage capability. Therefore, this work presents a more effective strategy for constructing high-performance MXene-based layered films.