Flexible, lightweight, robust, and multifunctional characteristics are greatly desirable for next-generation wearable electromagnetic interference (EMI) shielding materials. In this work, an alternating multilayered structure with robust polymer frame layers and directly contacted conducting layers was designed to prepare high-performance EMI films. Especially, the multilayered films containing alternating cellulose nanofiber (CNF) layers and MXene layers are fabricated via a facile and efficient alternating vacuum filtration approach. Deriving from the mechanical frame effect acted by CNF layers in, which is capable of preventing the nanosized “zigzag” crack in MXene layers from growing to the whole film, the alternating multilayered film (CNF@MXene) revealed the improved mechanical strength (112.5 MPa) and toughness (2.7 MJ m–3) compared to both freestanding MXene film and homogeneous CNF/MXene film. Meanwhile, the directly contacted MXene layers resulted in the increased electrical conductivity from 2 (homogeneous CNF/MXene film) to 621–82 S m–1 (CNF@MXene films). In conjunction with the extra “reflection-absorption-zigzag reflection” mechanism among the alternating multilayers, CNF@MXene films demonstrated an exceptional EMI shielding effectiveness of ∼40 dB in the X-band and K-band and high specific shielding effectiveness up to 7029 dB cm2 g–1 at a thickness of only 0.035 mm. Besides, the excellent mechanical flexibility ensured the stable EMI shielding and electrical properties, which can withstand the folding test more than 1000 times without obvious reduction. Moreover, the excellent electrical conductivity endows the alternating multilayered film with an outstanding and steady Joule heating performance, which could reach more than 100 °C at only 6 V impressed voltage to within 10 s. As a result, our alternating multilayered film with reinforced EMI shielding and Joule heating performance is promising in the next-generation intelligent protection devices applying in cold and complex practical environments.

Transparent conductive film (TCF) is promising for optoelectronic instrument applications. However, designing a robust, stable, and flexible TCF that can shield electromagnetic waves and work in harsh conditions remains a challenge. Herein, a multifunctional and flexible TCF with effective electromagnetic interference shielding (EMI) performance and outstanding electro-photo-thermal effect is proposed by orderly coating Ti3C2T x MXene and a silver nanowire (AgNW) hybrid conductive network using a simple and scalable solution-processed method. Typically, the air-plasma-treated polycarbonate (PC) film was sequentially spray-coated with MXene and AgNW to construct a highly conductive network, which was transferred and partly embedded into an ultrathin poly­(vinyl alcohol) (PVA) film using spin coating coupled with hot pressing to enhance the interfacial adhesion. The peeled MXene/AgNW-PVA TCF exhibits an optimal optical and electrical performance of sheet resistance 18.3 Ω/sq and transmittance 52.3%. As a consequence, the TCF reveals an effective EMI shielding efficiency of 32 dB in X-band with strong interfacial adhesion and satisfactory flexibility. Moreover, the high electrical conductivity and localized surface plasmon resonance (LSPR) effect of hybrid conductive network endow the TCF with low-voltage-driven Joule heating performance and excellent photothermal effect, respectively, which can ensure the normal functioning under extreme cold condition. In view of the comprehensive performance, this work offers new solutions for next-generation transparent EMI shielding challenges.

Electromagnetic (EM) pollution affecting people's normal lives and health has attracted considerable attention in the current society. In this work, a promising EM wave absorption and shielding material, MXene/Ni hybrid, composed of one-dimensional Ni nanochains and two-dimensional Ti 3 C 2 T x nanosheets (MXene), is successfully designed and developed. As expected, excellent EM wave absorption and shielding properties are obtained and controlled by only adjusting the MXene content in the hybrid. A minimum reflection loss of −49.9 dB is obtained only with a thickness of 1.75 mm at 11.9 GHz when the MXene content is 10 wt %. Upon further increasing the MXene content to 50 wt %, the optimal EM shielding effectiveness (SE) reaches 66.4 dB with an absorption effectiveness (SE A ) of 59.9 dB. Mechanism analysis reveals that the excellent EM wave absorption and shielding performances of the hybrid are contributed to the synergistic effect of conductive MXene and magnetic Ni chains, by which, the dielectric properties and electromagnetic loss can be easily controlled to obtain appropriate impedance matching conditions and good EM wave dissipation ability. This work provides a simple but effective route to develop MXene-based EM wave absorption and shielding materials. A universal guideline for designing the absorbing and shielding materials for the future is also proposed.

Two-dimensional Ti 3 C 2 T x MXene-based hybrids-anchored magnetic metal nanoparticles show a huge potential application as effective wave absorbers due to the synergistic electromagnetic (EM) loss effect. In this work, uniform and size-controllable nickel, cobalt, or nickel−cobalt alloy nanoparticles were in situ grown on the surface of MXene via a facile and moderate co-solvothermal method for the first time. As an example, a nickel nanoparticles-anchored MXene (Ni@MXene) hybrid was homodispersed into dielectric polyvinylidene fluoride to develop its EM waveabsorbing capacity to a great extent. As expected, the results showed strong reflection loss (RL min = −52.6 dB at 8.4 GHz), broad effective absorption bandwidth (EAB = 3.7 GHz including 71% of X-band), low loading (10 wt % Ni@MXene), and thin thickness (3.0 mm). By adjusting the sample thickness, EAB can cover completely the whole X-band with a maximum of 6.1 GHz, showing a huge potential of Ni@MXene hybrid applying as aircraft stealth coating. The mechanism analyses revealed that the excellent impedance matching, magnetocoupling effect, conductance, magnetic loss, and multiple scatterings contribute to the splendid EM wave-absorbing performance of the Ni@MXene hybrid. Considering the excellent overall performance, the Ni@MXene hybrid was identified as a promising candidate for EM wave absorption.

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