Ultrastrong and Highly Conductive MXene‐Based Films for High‐Performance Electromagnetic Interference Shielding

Abstract Ultrathin and flexible electromagnetic interference (EMI) shielding materials are urgently required to shield increasingly serious radiation pollution. Newly emerged 2‐dimensional transition‐metal carbides (MXenes) are promising for efficient EMI shielding due to their superb electrical conductivity, versatile surface chemistry, and layered structure. However, the mechanical performance of MXene films is not satisfactory for engineering applications, and the traditional reinforcement approaches usually cause serious reduction in electrical conductivity of the films. An efficient strategy is demonstrated to reinforce MXene films with graphene oxide, leading to enhanced interfacial interactions and more densely packed layered structures. The modified MXene film exhibits a high tensile strength of 209 MPa while maintaining its high electrical conductivity close to that of pristine MXene film. An outstanding shielding effectiveness of 50.2 dB is achieved at a small film thickness of 7 µm. Moreover, a facile technique is used to tune the wetting behavior of the modified MXene films. The water contact angle can be readily regulated from 65.7° to 95.7°. This film, with excellent EMI shielding performance and tunable wetting behavior, is highly promising for various applications in aerospace, flexible supercapacitors, and smart electronics.