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In response to the increasing utilization of communication technology, there is a growing need for electromagnetic interference (EMI) shielding materials to adapt to diverse application scenarios. In this study, the self‐destructible EMI shielding films (SEFs) that possess the unique capability to reduce conductivity and shielding efficiency through temperature elevation are introduced. The SEFs effectively fulfill the requirement of triggering EMI shielding failure under specific conditions, which can be achieved by simply spraying a mixture of thermally expandable microspheres (TEMs), conductive fillers, and resin substrates. The segregated structures resulting from the incorporation of TEMs confer exceptional electrical conductivity and superior EMI shielding performance at low conductive filler content. When the ambient temperature surpasses the glass transition temperature of the TEM shell, the thermally expandable characteristics cause a disruption in the conductive path of the SEFs, leading to a significant decline in shielding effectiveness. Additionally, the SEFs exhibit outstanding Joule heating effects (90 °C) at low voltage (1.5 V) within a brief time frame (10 s). Importantly, when employed as Joule heaters, the SEFs possess an intrinsic safety mechanism that automatically ceases operation in the event of circuit overload, thus minimizing any potential risks. [ABSTRACT FROM AUTHOR]

Highlights: The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment. A lightweight flexible thermally stable composite is fabricated by combining silica nanofiber membranes (SNM) with MXene@c-MWCNT hybrid film. The flexible SNM with outstanding thermal insulation are prepared from tetraethyl orthosilicate hydrolysis and condensation by electrospinning and high-temperature calcination; the MXene@c-MWCNTx:y films are prepared by vacuum filtration technology. In particular, the SNM and MXene@c-MWCNT6:4 as one unit layer (SMC1) are bonded together with 5 wt% polyvinyl alcohol (PVA) solution, which exhibits low thermal conductivity (0.066 W m−1 K−1) and good electromagnetic interference (EMI) shielding performance (average EMI SET, 37.8 dB). With the increase in functional unit layer, the overall thermal insulation performance of the whole composite film (SMCx) remains stable, and EMI shielding performance is greatly improved, especially for SMC3 with three unit layers, the average EMI SET is as high as 55.4 dB. In addition, the organic combination of rigid SNM and tough MXene@c-MWCNT6:4 makes SMCx exhibit good mechanical tensile strength. Importantly, SMCx exhibit stable EMI shielding and excellent thermal insulation even in extreme heat and cold environment. Therefore, this work provides a novel design idea and important reference value for EMI shielding and thermal insulation components used in extreme environmental protection equipment in the future. [ABSTRACT FROM AUTHOR]

Electromagnetic interference (EMI) shielding fabrics are crucial in addressing the increasingly serious electromagnetic pollution. To meet wearable requirements, stretchability and thermal comfortability are often desired, but which still are challenging. Herein, a stretchable EMI shielding fabric is fabricated via electrospinning coupled with biaxial pre‐stretching spraying, in which a block stacking wrinkled silver nanowire (AgNW)/Ti3C2Tx MXene network is coated on one side of electrospun thermoplastic polyurethane (TPU)/polydimethylsiloxane (PDMS) fabric. As expected, the wrinkled structure protects conductive network from fracture during stretching process, so as to realize the strain‐invariant electrical conductivity. Thus, the fabric exhibits a stretchable EMI shielding performance of over 40 dB when subjected to 10–50% uniaxial strains or 21–125% biaxial strains. More importantly, the white TPU/PDMS side and the black AgNW/MXene side enable the fabric passive radiative cooling and heating, respectively. The cooling side exhibits high mid‐infrared emissivity (97.5%) and solar reflectance (90%), thus reducing the skin temperature by ≈4.9 °C. The heating side with high solar absorptivity (86.6%) and photothermal effect increased the skin temperature by ≈5 °C. Therefore, the fabirc with stretchable EMI shielding and Janus‐type dual‐mode personal passive thermal management is promising in future wearable products. [ABSTRACT FROM AUTHOR]

[Display omitted] Ultrathin MXene composite films, with their flexibility, metal-level conductivity, and multifunction compatibility, are an ideal choice for electromagnetic interference (EMI) shielding materials in future developments. Nonetheless, the dilemma between electrical conductivity and robustness in these composite films remains a challenge. Herein, an ammonium polyphosphate (APP) assisted interfacial multiple cross-linking strategy, achieved via simple solution blending and filtration, was employed to reinforce and toughen the "brick–mortar" layered MXene/bacterial cellulose (MBCA) films without compromising their conductivity and EMI shielding ability. The introduction of a small amount of APP leads to multiple interfacial interactions between MXene and bacterial cellulose, resulting in significant enhancements in mechanical strength (360.8 MPa), Young's modulus (2.8 GPa), fracture strain (17.3%), and toughness (34.1 MJ/m3). Concurrently, the MBCA film displayed satisfactory conductivity values of 306.7 S/cm and an EMI SE value of 41 dB upon optimizing the MXene content. Additionally, the MBCA film demonstrated a consistent, rapid-response photothermal conversion capability, achieving a photothermal conversion temperature of 97 °C under a light intensity of 200 mW/m2. Consequently, this tough and multifunctional EMI shielding film holds substantial promise for protecting electronic equipment. [ABSTRACT FROM AUTHOR]

Flexible transparent conductive electrodes (TCEs) that can be used as electromagnetic interference (EMI) shielding materials have a great potential for use as electronic components in optical window and display applications. However, development of TCEs that display high shielding effectiveness (SE) and good stretchability for flexible electronic device applications has proven challenging. Herein, this study describes a stretchable polydimethylsiloxane (PDMS)/silver nanowire (AgNW) TCE with a fence‐like aligned conductive network that is fabricated via pre‐stretching method. The fence‐like AgNW network endowed the PDMS/AgNW film with excellent optoelectronic properties, i.e., low sheet resistance of 7.68 Ω sq−1 at 73.7% optical transmittance, thus causing an effective EMI SE of 32.2 dB at X‐band. More importantly, the fence‐like aligned AgNW conductive network reveals a high stability toward tensile deformation, thus gives the PDMS/AgNW film stretch‐stable conductivity and EMI shielding property in the strain range of 0–100%. Typically, the film can reserve ≈70% or 80% of its initial EMI SE when stretching at 100% strain or stretching/releasing (50% strain) for 128 cycles, respectively. Additionally, the film exhibits a low‐voltage driven and stretchable Joule heating performance. With these overall performances, the PDMS/AgNW film should be well suited for use in flexible and stretchable optical electronic devices. [ABSTRACT FROM AUTHOR]

Flexible transparent electromagnetic interference (EMI) shielding films in visual windows are crucial for the innovation of optoelectronic devices, but the challenge of balancing light transmittance and EMI shielding effectiveness (SE) still exists. Herein, this work described a flexible transparent MXene@SWNTs/PC film with a hierarchical conductive layer that was fabricated via an alternating rotation spraying method. The multi-scale hierarchical structure configured with 1D SWNTs and 2D MXene endow the obtained film with good comprehensive properties, i. e, low sheet resistance of 32.8 Ω/sq at 56.1% light transmittance, thus causing a satisfactory EMI SE of 20.8 dB. Moreover, the transparent shielding films exhibit remarkable flexibility, which can maintain steady EMI SE after 1000 continuous bending cycles. More importantly, the low sheet resistance and high light absorption capacity of hybrid conductive layer facilitate the transparent shielding film with low-voltage-driven electric heating effect and outstanding photothermal conversion ability, respectively, ensuring the normal operation under extreme cold condition. The combination of good light transmittance, satisfactory EMI shielding performance, and multi-source thermal response enables MXene@SWNTs/PC film to have great potential as a transparent shielding film in emerging optoelectronic devices. A multifunctional MXene@SWNTs/PC film with hierarchical structure prepared via an alternating rotation spraying process, integrating capabilities of light transmittance, EMI shielding, and multi-source thermal response together. [Display omitted] [ABSTRACT FROM AUTHOR]

Being as lightweight and thin as possible is highly desirable for electromagnetic interference (EMI) shielding materials in electronic devices as the high requirement in miniaturization and weight reduction. Constructing three-dimensional (3D) porous conductive architecture into two-dimensional (2D) film provides one of the feasible strategies. Herein, pyrolytic carbon aerogel films from aramid nanofiber (ANF) with novel skin-core structure containing compact film skin and 3D porous nanofiber network core were fabricated by a facile method. The abundant conjugate aromatic structure in backbone endows ANF-derived carbon aerogel film with a high conductivity of 1029.5 S/m. Remarkably, the high electrical conductivity, as well as the 3D porous skin-core structure, which not only constructs the interconnected electron transmission paths but also significantly extends the propagation path of EM waves, enables the carbon aerogel film a high EMI shielding effectiveness (SE) of 41.4 dB at low density (54.4 mg/cm3) and thin thickness (162 μm) with high specific shielding effectiveness (SSE/t) of up to 47122.6 dB cm2/g. Besides, ANF-derived carbon aerogel film exhibits an excellent photothermal conversion ability, which greatly broadens the application environment. More interestingly, the easy and flexible preparation method with adjustable film thickness, density and area makes large-scale production of carbon aerogel film possible. [Display omitted] • ANF-derived carbon aerogel film prepared by a facile and scalable method. • The film reveals skin-core structure with compact skin and nanofiber network core. • The carbon aerogel film exhibits high EMI SE at low density and thin thickness. • The carbon aerogel film shows an excellent photothermal conversion capacity. [ABSTRACT FROM AUTHOR]

• Magnetic TRGO@Ni hybrid was prepared by hydrothermal and in situ thermal reduction. • Nacre-like layered CNF/TRGO@Ni film was assembled via a facile vacuum filtration. • The film showed excellent conductivity, EMI shielding performance and flexibility. • Impedance mismatch, multireflection and synergetic loss are shielding mechanisms. Flexible and ultrathin electromagnetic interference (EMI) shielding films are urgently required to manage increasingly serious radiation pollution. In this work, the EMI shielding performance and flexibility of conductive polymer films were addressed by assembling magnetic graphene-based hybrid and cellulose nanofiber (CNF). Briefly, magnetic graphene hybrid anchored by Ni nanoparticles (TRGO@Ni) was synthesized by in situ thermal reduction. Then, highly flexible and ultrathin CNF/TRGO@Ni film with "brick-mortar" layered structure was assembled via a facile vacuum filtration method. As expected, CNF/TRGO@Ni film with 50 wt% filler loading exhibits an enhanced electrical conductivity (262.7 S/m) and EMI shielding effectiveness (32.2 dB) comparing to CNF/TRGO film. Moreover, the excellent mechanical flexibility of CNF/TRGO@Ni film results in that the electrical conductivity and EMI SE only declines by 7.5% after bending 1000 cycles. The EMI shielding mechanism is attributed to the combination of enhancing impedance mismatch, multireflection in "brick-mortar" lamellar structure and endowing synergetic loss by graphene and Ni nanoparticles. [ABSTRACT FROM AUTHOR]

Enormous electromagnetic pollutions emerge with the rapid development of electronic technique, high-performance electromagnetic interference (EMI) shielding composites are greatly desired to protect human and precision instruments from electromagnetic interference. Here we fabricated a lightweight, porous carbon fiber felt/Ag/polydimethylsiloxane (CFF/Ag/PDMS) composite film via electroless plating and dip-coating method. The obtained homogenously distributed Ag nanoparticles on the surface of carbon fibers and the porous structure of CFF endow the film with excellent electrical conductivity and superior EMI shielding effectiveness (EMI SE). The maximum electrical conductivity and EMI SE value of the composite film with a thickness of 0.21 mm reach 540.9 S/cm and 105 dB at 8.2–12.4 GHz (X-band), respectively. Benefitting from the encapsulation of PDMS, the composite film exhibits outstanding corrosion resistance and oxidation resistance. Particularly, the composite film also exhibits excellent electro/photo-thermal conversion effect with outstanding heating controllability, cyclic stability, which shows great potential in 5 G communication technology and thermal management. • A three-dimensional porous conductive network was constructed via polydopamine-assisted electroless plating. • The electromagnetic shielding effectiveness (EMI SE) of the composite film could reach 105 dB over 8.2–12.4 GHz. • The EMI SE of composite film remained stable in high temperature, strong acid and alkali environments. • The composite films exhibit excellent electro-thermal and photo-thermal conversion properties. [ABSTRACT FROM AUTHOR]

Constructing surface hierarchical layer is regarded as an effective surface modification of carbon fibers (CFs) to enhance their composites mechanical properties. However, this method usually deteriorates the intrinsic properties of CF and the hierarchical layer is not fully compatible with thermal processing of the polymer. Here, a novel hierarchical layer consisting of polydopamine, polyethyleneimine and multi-walled carbon nanotubes without damages to CF was successfully decorated on CF surface (CNT@PP-CF) for simultaneously enhancing the mechanical and the electromagnetic interference (EMI) shielding properties of CF reinforced polyamide 66 (PA66) composite. The CNT@PP hierarchical layer with dynamic imine bonds enhanced the interfacial wettability and bonding between CF and PA66 during thermal processing. Compared with that of untreated-CF, the interfacial shear strength and tensile strength of CNT@PP-CF/PA66 composite were increased by 52.3% and 19.2%, respectively. Meanwhile, the EMI shielding performance was enhanced by 89.6%. This improvement would be ascribed to the dynamic imine polar groups and heterogeneous interfaces in the hierarchical layers which enhanced the conductive and dielectric losses of composites. Our research provided a novel approach based on dynamic covalent bond exchanges to achieve the functional and structural integration of CF reinforced thermoplastic resin composites. [Display omitted] • A new hierarchical layer modified method based on dynamic imine bond was proposed. • Dynamic imine bonds exchanges improved the interfacial properties of composite. • Mechanical properties and EMI shielding performance were enhanced simultaneously. • This method is suitable for CF/thermoplastic composites during thermal processing. [ABSTRACT FROM AUTHOR]

With the rapid development of new-generation wireless communication technologies and portable intelligent electronic devices, the development of composites with excellent thermal conductivity and electromagnetic shielding properties has become an urgent challenge. In this work, a unique fibers-induced segregated-like structure strategy for fabricating thermoplastic polyurethane/polydopamine/silver (TPU/PDA/Ag) composites film with high thermal conductivity (TC) and excellent electromagnetic interference (EMI) shielding performance is demonstrated via electrospinning-electroless depositing-pressing technology. The TPU/PDA/Ag composites film exhibit excellent in-plane TC of 20.9 W/(m⋅K) at 75 wt% Ag loading, which shows excellent thermal management capability as heat spreaders of high-power light-emitting diode (LED) modules in practice. Meanwhile, the composites film presents outstanding EMI shielding efficiency of 109 dB (8.2–12.4 GHz) with a thickness of 45 μm and prominent EMI shielding reliability after 1000 cycles of bending. In addition, the composites film shows good tensile strength (12.1 MPa), elongation at break (108.0%), and toughness (11.59 MJ/m3). The obtained TPU/PDA/Ag composites film achieves the desired balance among thermal conductivity, EMI shielding, and mechanical properties, indicating broad application prospects in new-generation wireless communication technologies and portable intelligent electronic devices. [ABSTRACT FROM AUTHOR]

• Synergistic MXene/CNTs based multifunctional TPU fabric (MCT-fabric) was prepared. • The MCT-fabric strain sensor shows both high sensitivity and broad sensing range. • The MCT-fabric shows superior EMI shielding effectiveness. • The MCT-fabric shows high efficient and long-term stable Joule heating capability. High-performance electronic textile with outstanding strain sensing, electromagnetic interference (EMI) shielding, and Joule heating performances are highly desirable for modern integrated smart wearable electronic devices. Herein, multifunctional electronic textile based on hybrid Ti 3 C 2 T x MXene and carbon nanotubes (CNTs) conductive nanomaterials coated thermoplastic polyurethane (TPU) non-woven fabric (MCT-fabric) is fabricated via a facile dip-coating approach. Based on the synergistic MXene/CNTs conductive coating and pre-stretching induced ultrasensitive microcrack structure, tunable conductive MCT-fabric strain sensor with high sensitivity (GF is as high as 9022), wide sensing range (∼210 %), rapid response/recovery time (140/160 ms), excellent long-term stability and reliability (∼1000 cycles) is successfully constructed. Besides, benefiting from the perfect synergistic conductive network and porous fibrous network structure, the MCT-fabric displays superior EMI shielding effectiveness (∼43 dB for the MCT-fabric with a thickness of 600 μm) and excellent thermal management performance including high Joule heating temperature at relatively low applied voltages, rapid Joule heating response, sufficient heating stability and reliability. This work indicates that the high-performance multifunctional electronic textile has attractive potential for strain sensing, EMI shielding and thermal management applications in artificial intelligence and emerging wearable electronics. [ABSTRACT FROM AUTHOR]

The rapid development of electronic devices has led to widespread demand and research on electronic packaging materials with electromagnetic shielding and thermal conductivity (TC) properties due to the inevitable issues of the electromagnetic radiation and thermal accumulation. However, there exists a huge challenge to simultaneously achieve high electromagnetic shielding and TC as well as the electrical insulation requirement as electromagnetic shielding predominantly relies on electrical conductivity of materials. Multilayer structure can endow composite materials with a variety of properties. Therefore, in this work, we fabricated sandwiched cellulose nanofiber/boron nitride nanosheet/Ti 3 C 2 T x MXene films by using a simple and effective alternating vacuum filtration method, and as a result, the special sandwich structure endows the film with excellent electromagnetic shielding, insulation and TC performance. The composite film has an extremely high electromagnetic shielding effectiveness up to 60.7 dB at 8.2 GHz as well as still maintains good electrical insulation properties due to the presence of the CNF/BNNS layer on the surface. Moreover, when the content of BNNS in the CNF/BNNS layer reaches 70 wt%, the sandwiched film has excellent in-plane TC of 19.97 W m−1 K−1. The sandwiched film with excellent electromagnetic shielding and high TC yet insulation performance has great application value in highly integrated electronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Multifunctional and superhydrophobic cellulose composite paper (CCP) is fabricated. • CCP shows a high EMI shielding effectiveness and electrical conductivity. • The superhydrophobic surface is used as the hydraulic triboelectric nanogenerator. • Surface temperature of CCP can reach 140 °C with a applied voltage of 6 V. Cellulose-based materials have attracted tremendous interest recently due to their fascinating merits of renewability, biodegradability, and low cost, holding great promise in electromagnetic protection, clean energy harvesting, and thermal management. However, the simple and effective integration of multiple functions into single cellulose material remains a challenge. Herein, we report the fabrication of a multifunctional and superhydrophobic cellulose composite paper (CCP) via coated MXene modified by in-situ polymerized polypyrrole and PDMS/candle soot on the opposite surface of the paper. CCP exhibits high-performance electromagnetic interference shielding effectiveness (~40 dB) while maintaining high electrical conductivity (1467 S/m). Moreover, the superhydrophobic surface of CCP can be used as the hydraulic triboelectric nanogenerator (H-TENG) to harvest water energy due to the liquid–solid contact triboelectrification and electrostatic induction. The hydraulic triboelectric energy can be captured and released when water droplets drop from a height of 2 cm and roll at a tilt angle of 20°, the output current can reach a peak of 0.8 nA. Furthermore, the surface saturation temperature of CCP can reach 140 °C with a low applied voltage of 6 V enabled by the Joule effect. Thus, CCP holds great potentials in applications of integrated smart electronics, clean energy harvesting, and thermal management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrostatic absorption and thermal-cladding assist tight bonding of CNT on TPU. • Segregated CNT/TPU composite exhibits EMI SE of 49.4 dB with only 3.7 wt% CNT. • EMI SE and EM wave absorption are improved by introducing a Ag reflection layer. • Asymmetric TPU/CNT/Ag composites possess excellent EMI SE of 79.4 dB and the lowest reflection of 0.54. Absorption-dominated electromagnetic interference (EMI) shielding composites with high shielding effectiveness (SE) and low reflection (R) is of particular interests for next-generation electronic devices, but it remains a great challenge. Herein, an ingenious approach is proposed to develop asymmetric thermoplastic polyurethane (TPU)/carbon nanotube (CNT)/Ag composites comprised of a segregated TPU/CNT composite layer and a conducting silver layer through the combination of electrostatic absorption, thermal-cladding, vacuum-assisted hot compression, and blade-coating methods. By high-speed mixing of charged CNT and TPU granules and vacuum-assisted compression molding, a segregated TPU/CNT composite layer with highly compacted CNT paths is constructed, which provides efficient electromagnetic wave absorption performance. Further introducing a silver coating serves as a reflection layer, resulting in a special "absorb-reflect-reabsorb" course when electromagnetic waves penetrate the asymmetric composite. The synergistic effects contribute to a preeminent EMI SE of 79.4 dB and SE A of 74.8 dB against the X-band at extremely low filler content (3.7 wt% CNTs and 0.04 wt% Ag) of the asymmetric TPU/CNT/Ag composites, which indicates 99.999999% EM waves are attenuated in the propagation process, and SE A contributes 94.2% to the total SE. Moreover, an R-value of 0.54 is reached because of the destructive interference between the reflected and incident EM waves. This work opens an avenue for the design and fabrication of EMI shielding CPCs with reliable absorption-dominated features and is highly promising for applications in next-generation electronic devices. [ABSTRACT FROM AUTHOR]

The durability and large-scale production of Ti 3 C 2 T x MXene-based composites are the main obstacles in industrialized application. Herein, a scalable blade coating method is demonstrated for fabricating the flexible and durable polyvinylidene fluoride (PVDF)/Ti 3 C 2 T x MXene layered films with compact hierarchical brick-and-mortar structure. The highly aligned MXene nanosheets make the obtained PVDF/MXene films with high electrical conductivity from 21.1 to 214.6 S cm−1. In combination to the multiple wave reflection in hierarchical layered structure and the interfacial polarization between dielectric matrix and MXene, PVDF/MXene films reveal excellent electromagnetic interference (EMI) performance with an optimal specific EMI shielding effectiveness (SSE/t) of 19504.8 dB cm2 g−1 at only 17 μm thickness. More importantly, the PVDF/MXene film can withstand the damages from mechanical deformation, hot/cold attack and chemical corrosion, meanwhile maintain a stable EMI shielding performance within floating of 5%. Besides, arising from the surface plasmon resonance effect and high electrical conductivity, the PVDF/MXene film reveals photo/electro-thermal heating abilities with rapid response time, high stability and controllability, which ensure their reliable EMI shielding performance under extremely cold conditions. [Display omitted] • A scalable blade coating method was reported for fabricating PVDF/MXene layered film. • The film with compact brick-and-mortar structure reveals good EMI shielding property. • PVDF/MXene film shows superior durability with stable EMI SE in various environments. • PVDF/MXene film exhibits multifunctional photo/electro-thermal conversion capacities. [ABSTRACT FROM AUTHOR]

Hybrid fillers of different geometries are increasingly utilized for the development of functional polymer composites. We herein report the role of HDPE-g-MAH as a compatibilizer for ternary composites consisting of HDPE, multi-walled carbon nanotubes and hexagonal boron nitride (BN). Through melt blending, HDPE-g-MAH can reduce the agglomeration of fillers and facilitate the formation of network structure. Due to the synergistic effect, ternary composites have demonstrated significantly higher thermal conductivity than those binary composites, and their maximum increase relative to the matrix is 262%. The mechanical performance and thermal conductivity are explained from perspectives of the morphology and crystallinity of the composites. The rheological properties of both binary and ternary composites have close relationship with their thermal conductivity. Although a high fraction of BN nanosheets can greatly reduce the electrical conductivity of ternary composites, they posed little effect on the electromagnetic interference shielding performance, owing to their electrical insulating nature. This research can provide new clues for the development of functional materials. Image 1 [ABSTRACT FROM AUTHOR]

With the rapid development of the flexible electronics industry, the range of multifunctional applications of materials has become extensive. But it is still a challenge to apply flexible materials to different fields while ensuring corresponding performance. Herein, a simple and available approach is addressed to fabricate conductive polymer composite films supported on Ag flakes and waterborne polyurethane (WPU) by spraying. The WPU/Ag films with uniform structure show outstanding flexibility and electromagnetic interference shielding effectiveness of 68.9 dB with thickness of only 50 μm, and could sustain a high standard even undergoing excessive mechanical deformations. Besides, the resulted films possess prominent electro-thermal effect, which can achieve a temperature of over 120 °C by applying a low voltage of 2 V, and the heat can be dissipated rapidly along with the connecting Ag network. Moreover, it shows a high gauge factor (229.2), good durability and reproductivity (over 1000 cycles), and rapid response time to strain (50 ms), which can be potentially used in the field of human movement monitoring and wearable electronic devices. These results indicate the multifunction of the WPU/Ag film, which could widen its practical applications after the corresponding treatment. Image 1 • Multifunctional WPU/Ag composite films were prepared by the solution blending and spraying technique. • The film with a thickness of 50 μm exhibits superior conductivity (1101.32 S cm−1) and EMI SE (68.97 dB). • The film can be rapidly heated to 125 °C under 2.0 V at 1 min. • The film shows high gauge factor (229), goodreproductivity (over 1000 cycles), and rapid response time (50 ms). [ABSTRACT FROM AUTHOR]

Developing multifunctional transparent shielding films (TSFs) are highly desirable for the advanced visualization electronic devices. Herein, based on the excellent electrical conductivity of two-dimensional Ti 3 C 2 T x (MXene), flexible hydrophobic MXene-based transparent conducting films are applied in the field of shielding electromagnetic wave and electrical heating. Typically, a spraying coupled with spinning technique is demonstrated to orderly deposit MXene and hydrophobic fumed silica (Hf-SiO 2) on transparent polycarbonate (PC) for developing the multifunctional TSFs. The obtained sandwich structural PC/MXene/Hf-SiO 2 film exhibits the balanced optical and electrical properties with a low electrical resistance of 35.1 Ω/sq and corresponding transmittance of 33.4%, showing an effective electromagnetic interference shielding effectiveness (EMI SE > 20 dB) combined with a rapid steady joule heating performance at safe voltages (~100 °C at 13 V), simultaneously. Meanwhile, the superhydrophobic Hf-SiO 2 coating layer not only endows the film with excellent self-cleaning ability, but also prevents MXene from oxidation. As a result, the hydrophobicity, conductivity and shielding performance of this film can steadily maintain in outdoor conditions for 100 days. Besides, outstanding flexibility gives the film with superior mechanical fatigue resistance (<10% resistance change after mechanical bending 1000 cycles). This work opens a new avenue for preparing next-generation multifunctional TSFs to meet the various application environments. Image 1 [ABSTRACT FROM AUTHOR]

• Introduction of iron ionic yielded stronger Fe 3 O 4 @graphene aerogel with excellent EMISE. • Enhancement of mechanical properties was attributed to Fe-N x complex and flower Fe 3 O 4 coating. • Both reduction of graphene oxides and coating of Fe 3 O 4 improved the EMI shielding properties. The graphene oxides would be reduced by dopamine self-polymerization to self-assembly graphene hydrogel and the graphene building blocks were covered with polydopamine. In order to obtain stronger aerogel with excellent electromagnetic interference shielding effectiveness (EMISE), bioinspired by mussel byssus, Fe3+/Fe2+ were introduced into the preparation process. Fe ionic endowed the aerogel with a remarkable combination of high hardness and extensibility by hydroxyl/amine-Fe3+ chelation cross-links. When PH = 10, the Fe 3 O 4 in-situ coated on the aerogel surface, which also enhanced the mechanical and magnetic loss properties of aerogel. After pyrolysis under 800 °C, Fe-N coordination complex and stable Fe 3 O 4 still exhibited mechanical strengthening effect. As for EMISE, Fe/N doping and flower-like Fe 3 O 4 were also beneficial for dielectric and magnetic polarity, thus improved its related properties. Compared with that of pristine graphene aerogel, the compressive strength of 4 mg/mL Fe3+ induced Fe 3 O 4 @graphene aerogel under 50% strain increased by 22.9% and high compressive recoverability under 90% strain was observed. The EMISE was also improved over wide band range of 2–18 GHz. For high frequency, SE value of samples with 2 mm thickness was as high as 41 dB. Furthermore, owing to annealing process, it could be inferred that it would be applied in high temperature filed. [ABSTRACT FROM AUTHOR]

• Flexible HAMS films with alternant graphene and Ni chains were designed firstly. • High-effective electrons and phonons conductive paths were formed in HAMS films. • HAMS films reveal remarkable EMI shielding and thermal conductivity simultaneously. • Stacking hot-pressing for preparing HAMS films is easy to large-scale application. Flexible polyvinylidene fluoride (PVDF) films with various heterogeneous alternating multilayer structure (HAMS) containing high-aligned graphene nanosheets and Ni nanochains were designed for electromagnetic interference (EMI) shielding and heat dissipation applications. Because of the unique structure and highly aligned nanofillers, effective electron and phonon conductive paths were formed in HAMS films with optimal electrical and thermal conductivity of 76.8 S/m and 8.96 W/mK, respectively. Combining the high electrical conductivity and the synergetic electromagnetic loss, as well as multi-level electromagnetic multireflection, the optimal HAMS film with thickness of 0.5 mm exhibits a high EMI shielding effectiveness (SE) of 43.3 dB, showing 98.6% increment compared to homogeneous film (21.8 dB), which can further improve to 51.4 dB when increasing the thickness to 0.7 mm. Simultaneously, the highly concentrated and aligned graphene in alternating layers can contribute to the significant improvement in in-plane thermal conductivity of HAMS films with 14.3% and ~1200% increment comparing to the homogeneous film (7.84 W/mK) and pure PVDF (0.69 W/mK), respectively. Considering the outstanding performance and high-efficiency stacking hot-pressing preparation technique, HAMS films with alternating aligned graphene/Ni nanochain layers present a huge potential in practical large-scale application as advanced EMI protection and thermal management materials. [ABSTRACT FROM AUTHOR]