Ultrathin nanocomposite films with asymmetric gradient alternating multilayer structures exhibit superhigh electromagnetic interference shielding performances and robust mechanical properties

Multifunctional CoFe2O4@MXene-AgNWs/Cellulose Nanofiber Composite Films with Asymmetric Layered Architecture for High-Efficiency Electromagnetic Interference Shielding and Remarkable Thermal Management Capability

“…Constructing perfect electron or phonon transfer paths in materials is essential to acquiring desirable EMI SE and TC. Although metallic materials possess high-performance EMI shielding and thermal management capability, their inherent shortcomings of high density, easy corrosion, difficult processing, and inferior flexibility tremendously constrain their practical applications. , Nowadays, conductive polymer composites (CPCs) have attracted considerable attention and have been regarded as prospective alternatives for metallic materials because of their low density, anticorrosion, facile processability, and tunable properties. ,, Nevertheless, realizing high-performance EMI shielding and superior TC for CPCs usually requires high filler loadings, which irreversibly results in a sharp deterioration of the mechanical behavior, an increased thickness, and low affordability. , Numerous studies have certified that combining dielectric and magnetic fillers could synergistically enhance the attenuation capacity of electromagnetic waves (EMW) owing to the electromagnetic double dissipation effect. − Although the electric/magnetic hybrid CPCs can significantly enhance EMI SE, it still is a daunting task to obtain high EMI shielding performance with superior EMW absorption because the regulation of impedance matching is difficult in a homogeneous structure with constant conductivity. ,, Consequently, developing CPCs with high-efficiency EMI SE entailing strong EMW absorption remains challenging.…”

“…Various structural designs, such as segregated structure, , porous structure, , and layered structure, , have been adopted recently to reconcile the conflict between high-efficiency EMI SE and low reflection. The construction of segregated and porous structures can drastically mitigate the surface EMW reflection, but the issues of inferior mechanical properties, thick shielding thickness (usually exceeding 2.0 mm), and poor flexibility greatly restrict their practical applications in sensitive electronic instruments packed with highly integrated circuits.…”

“…Great efforts have been made by incorporating functional fillers such as transition metal carbides and/or nitrides (MXene), graphene nanosheets, carbon nanotubes, and silver nanowires (AgNWs) into the polymer matrix. Among them, the newly emerged two-dimensional (2D) MXene with satisfactory hydrophilicity, large specific area, metallic-like conductivity, and abundant native defects has aroused widespread attention in the EMI shielding field. − Meanwhile, AgNWs are widely used to construct CPCs with notable EMI SE and TC owing to their ultrahigh aspect ratio, brilliant electrical conductivity, remarkable heat transfer, and excellent mechanical characteristics. ,,− The design of an asymmetrical structure could combine the advantages of individual components fully and control the distribution of functional filler in a special layer, which can eliminate the restriction of the nonadjustable reflection feature in EMI shielding materials with fixed impedance matching. In addition, the asymmetrical architecture presents versatility owing to the different chemical compositions and microscopic morphologies on two sides. ,− Consequently, the construction of an asymmetric layered structure may be an ideal approach to obtaining multifunctional CPCs with high-efficiency EMI SE entailing strong EMW absorption and superior thermal management capability simultaneously.…”

Flexible and Robust Ti3C2Tx/(ANF@FeNi) Composite Films with Outstanding Electromagnetic Interference Shielding and Electrothermal Conversion Performances

“…[22] The electricmagnetic compounding of conductive and magnetic particles can effectively improve the impedance matching and electromagnetic recombination losses through the electromagnetic synergy, leading to the enhanced EMI SE. [23][24][25] Iron, cobalt, and nickel, as well as their oxides and alloys, are commonly used magnetic particles. [26][27][28] The magnetic nanoparticles possess combined advantages of high saturation magnetization, high Curie temperature, and high permeability and show important application values in EMI shielding and radar absorption fields.…”

“…[ 22 ] The electric–magnetic compounding of conductive and magnetic particles can effectively improve the impedance matching and electromagnetic recombination losses through the electromagnetic synergy, leading to the enhanced EMI SE. [ 23–25 ]…”