Low Filler Content Research Articles

Моделювання перколяційної поведінки теплопровідності у полімерних нанокомпозитах, які містять вуглецеві нанотрубки

An overview of the most correct mathematical models for describing the thermal conductivity of polymer-carbon nanotube systems, which characterize percolation behavior, is given. It is shown that the Landauer model, which does not take into account the presence of a percolation transition at low filler concentrations, is in poor agreement with the experiment. The sigmoidal model describes experimental data well, but is purely empirical. Zhang's model turned out to be incorrect for this type of system, as it was designed for a system with a high filler content. The scaling model showed good agreement with experimental data for a system with a low percolation threshold.

Solid epoxy for functional 3D printing with isotropic mechanical properties by material extrusion

Material extrusion is the most commonly used additive manufacturing process. However, currently it is mainly applied for the production of prototypes or simple jigs and fixtures due to issues with anisotropic material behavior. Diffusion and entanglement of the polymer chains is limited between the layers and among the infill lines within a layer of the usually thermoplastic material as it solidifies immediately after deposition. This results in weak bonding leading to a reduced load-bearing capacity. In this study, a thermosetting polymer is developed and presented. It enables cross-linking over the interfaces between the infill lines and layers during post-curing which resolves this issue. The formulation is based on a solid epoxy resin, allowing it to be processed in filament form and a latent curing agent preventing it from curing within the hotend and ensuring a suitable shelf life. To benchmark the newly developed material it is compared to casted and milled bulk specimens and 3D printed specimens with commercial thermoplastic filaments. Tensile tests and micrographs of the fracture surfaces prove the mechanical isotropy of the solid epoxy formulation. In addition, the material formulation is modified with single-walled carbon nanotubes to add electrical conductivity and allow functional 3D printing. Due to the high aspect ratio of the nanoparticles, a significantly lower filler content is necessary compared to the commercial materials. However, an electrical anisotropy is still observed as the material remains in a solid state during post-curing to retain its shape which limits the mobility of the nanoparticles and suppresses the agglomeration needed for conductive network formation after thorough dispersion. Proof of concept studies show that the functionalized material can be used in temperature and strain sensing applications. • Solid epoxy filament for low-cost material extrusion printers. • Isotropic material properties in material extrusion. • Nanoparticle modification for functional 3D printing with new generation materials. • Temperature and strain sensing applications.

Biomass-derived ultralight superior microwave absorber Towards X and Ku bands

Biomass-derived microwave absorbers have attracted extensive attention due to their natural abundance, low cost and eco-friendliness. However, it is still a challenge to achieve superior absorptivity under the extremely low filler content in such absorbers. Herein, we engineer a hybrid of Co3Fe7 alloy nanoparticles (NPs) anchoring on the biomass shaddock peel derived porous carbon nanosheets (CNs) for superlight and efficient microwave absorption. The CNs exhibit attractive graphene-like morphology with Co3Fe7 alloy NPs uniformly dispersing throughout the CNs. It is revealed that the EM parameters could be well controlled by tailoring the deposition ratio of Co3Fe7 NPs to optimize impedance matching. Specifically, the sample with relatively sparse Co3Fe7 NPs exhibit a reflection loss (RL) of –22.3 dB and broad absorption bandwidth of 5.3 GHz in Ku band under the ultralow filler content of only 8.0 wt%. As the deposition ratio of magnetic Co3Fe7 NPs increases, the optimized absorption peak moves to X band with −50.6 dB of RL value and 4.5 GHz of effective absorption, completely covering the whole X band. The elaborative studies demonstrate the significant influence of impedance matching on the ultimate absorption performance. This work paves a new way for the development of biomass-derived composites as superlight and tunable microwave absorber.

The effect of polymer molecular weights on the electrical, rheological, and vapor sensing behavior of polycarbonate/multi‐walled carbon nanotube nanocomposites

AbstractConductive polymer composites (CPCs) based on polycarbonate/multi‐walled carbon nanotubes (PC/MWCNT) were fabricated by melt mixing. By selecting the PCs with different molecular weights, three kinds of PC/MWCNT composites were obtained. The CPCs containing low viscous PC (lPC) had the lowest percolation threshold (0.06 vol%) as compared to those of medium viscous PC (mPC) (0.07 vol%) and high viscous PC (hPC) (0.13 vol%), which was attributed to the best MWCNT dispersion in matrix. Light microscopy images also demonstrated that lPC/MWCNT composite had the smallest undispersed filler agglomerates than the other two corresponding PC/MWCNT composites with the same filler loading (0.25 wt%). In terms of rheological measurements, rheological percolation occurred at a lower filler content for lPC/MWCNT than mPC/MWCNT and hPC/MWCNT composites. The chemo‐resistive properties of composites towards organic vapors were investigated by measuring relative resistance change of CPCs upon vapor immersion‐drying cycles. CPCs exhibited different sensing tendencies towards different organic vapors. lPC based CPCs exhibit higher relative resistance change as compared to mPC and hPC based CPCs because of their loosely overlapped conductive network, which are easily changed under polymer swelling. Besides, sample thickness is another factor that determined the vapor sensing performance of CPCs. Furthermore, relative resistance change of composites is found to be closely related with vapor concentration. This work presents a new thought in understanding filler dispersion in PC with different molecular weights, which has implication of turning conductive network structure and sensing performance of composites.

PEDOT:PSS/MXene/PEG composites with remarkable thermal management performance and excellent HF-band & X-band electromagnetic interference shielding efficiency for electronic packaging

Recently, the miniaturization of microelectronics has proposed a more urgent demand for the multi-functionalization of packaging materials. Here, a PEDOT:PSS/MXene/PEG composite, which is prepared by vertical directional freezing and vacuum infiltrating, integrates the function of heat management & EMI shielding into single packaging material. The melting & cooling enthalpy (237.6 & 236.1 J g−1) and the phase transition temperature of composite are enhanced synchronously for the first time. The zigzag modification of polyethylene glycol (PEG) crystal is induced by poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The rest of crystal with (7/2) helix conformation packs preferentially along the (120) plane. The stability of the melting composite is enhanced. The PEG leakage is less than 0.66 %, and over 80 % dimension is maintained under the pressure of 1.88 kPa. The composite shows excellent photo-thermal (η = 94.9 %) and electro-thermal (tη = 7.86) conversion performances. The EMI shielding mechanism is reflection-dominated and the total EMI shielding effectiveness (SET) of composite is 29.8 dB at the framework content as low as 1.22 wt%, which is the relatively low filler content and the highest enthalpy efficiency among the reported composites with the equivalent SET. The HF-band shielding capability of composite is verified by the Tesla kit. The assembled heterogeneous asynchrony photo-thermal-electric conversion system identifies its potential application on photo-thermal converters and heat buff. The HF-band & X-band (Sub-6G) EM waves shielding and heat management in microelectronics can be achieved simultaneously by applying this composite.

Meringue‐Inspired Fabrication of Highly Thermally Conductive BNNSs/SiCNWs/Epoxy Composites with Shape‐Programmable 3D Networks

AbstractThe construction of effective heat transfer routines is becoming more important because of the fast development of modern electronics. However, traditional network templates with fixed size cannot meet the various demands on the shape of products. Herein, a facile construction of a shape‐programmable 3D thermal network for epoxy composites is provided from the inspiration of meringue. Driven by the synergistic effect of silicon carbide nanowires (SiCNWs) and boron nitride nanosheets (BNNSs), the thermal conductivity (TC) of BNNSs/SiCNWs/epoxy composites with a 3D network is successfully enhanced to 0.69 W m–1 K–1 at low filler content (2.78 wt%), 3.8 times in comparison with neat epoxy, and the η (TC efficiency of filler) reaches 101. Meanwhile, the mechanical and thermal properties of composites are also enhanced (E' from 2.47 GPa (epoxy) to ≈3.50 GPa, Tg from 123 to 137 °C at 2.78 wt% BNNSs/SiCNWs content). This method may offer a promising prospect for the application in thermal management fields.

Enhanced Electromagnetic Shielding and Thermal Conductive Properties of Polyolefin Composites with a Ti3C2Tx MXene/Graphene Framework Connected by a Hydrogen-Bonded Interface.

The rapid increase of operation speed, transmission efficiency, and power density of miniaturized devices leads to a rising demand for electromagnetic interference (EMI) shielding and thermal management materials in the semiconductor industry. Therefore, it is essential to improve both the EMI shielding and thermal conductive properties of commonly used polyolefin components (such as polyethylene (PE)) in electronic systems. Currently, melt compounding is the most common method to fabricate polyolefin composites, but the difficulty of filler dispersion and high resistance at the filler/filler or filler/matrix interface limits their properties. Here, a fold fabrication strategy was proposed to prepare PE composites by incorporation of a well-aligned, seamless graphene framework premodified with MXene nanosheets into the matrix. We demonstrate that the physical properties of the composites can be further improved at the same filler loading by nanoscale interface engineering: the formation of hydrogen bonds at the graphene/MXene interface and the development of a seamlessly interconnected graphene framework. The obtained PE composites exhibit an EMI shielding property of ∼61.0 dB and a thermal conductivity of 9.26 W m-1 K-1 at a low filler content (∼3 wt %, including ∼0.4 wt % MXene). Moreover, other thermoplastic composites with the same results can also be produced based on our method. Our study provides an idea toward rational design of the filler interface to prepare high-performance polymer composites for use in microelectronics and microsystems.

Morphology, Deformation, and Micromechanical Behavior of Electrospun Nano‐hydroxyapatite Blended Biohybrid Scaffolds

AbstractFor bone tissue engineering, nano‐hydroxyapatite (nano‐HAp) is a widely used bioceramic filler in polymer fibrous scaffolds that changes the morphology and micromechanical behavior of fibers. In this study, different volume fraction percentages of nano‐HAp and vitamin D3 (VD3) are incorporated into electrospun polymer blend fibrous scaffolds comprising polycaprolactone (PCL), poly‐L‐lactic acid (PLLA), and gelatin (GEL). Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and uniaxial tensile testing are used to characterize the chemical, morphological, and micromechanical properties of the scaffolds. The FTIR analysis showed the presence of functional groups of fillers and polymers and their molecular interactions in the fibers. In the microscopic analysis, the fillers are found to affect the fiber morphology (including diameter, phase separation, and texture) and the response of the fibers under tensile deformation. The addition of 3% by volume of filler suspension results in maximum diameter of 4.34 µm, and the addition of 6%–12% filler leads to an increase in tensile strength from 0.7 to 5.6 MPa and strain at break from 2% to 37% for the composite fibers compared to neat fibers. The crazing behavior of the fiber is more noticeable at a low filler content (0%), whereas thin‐layer yielding becomes predominant at a higher filler content (12%). Thus, the study shows that scaffold fibers undergo brittle‐to‐ductile transitions as the filler percentage in the polymer blend increases from 0% to 12%. It has been further found that morphogens used as growth factors can be easily released from hydroxyapatite after adsorption.

Thermal conductivities of Ti3C2Tx MXenes and their interfacial thermal performance in MXene/epoxy composites – a molecular dynamics simulation

Ti-based MXene has been widely investigated for its excellent electronic properties but the thermal performance of Ti3C2Tx still remains uncharted on the molecular scale, which could significantly affect the thermal conductivity of their composites. This work adopted molecular dynamics method and effective medium theory (EMT) to analyze the thermal conductivity of 4 types of MXenes, including Ti3C2, Ti3C2F2, Ti3C2O2 and Ti3C2(OH)2, as well as their epoxy composites. The results showed that the terminal groups could reduce the phonon scattering in MXenes which could increase the thermal conductivity and also the interfacial affinity between MXene and epoxy molecules by improving interfacial binding energy. The Ti3C2O2 has the highest thermal conductivity of 140.25 Wm−1K−1, while Ti3C2(OH)2 has the lowest interfacial thermal resistance, which could lead a higher thermal conductivity in composite when its flake was under the critical size. The EMT results showed that Ti3C2O2 could significantly improve the TC of epoxy under a lower filler content; and the MD simulation parameters were validated by the comparison between other works and EMT prediction in this work. The current study provides suggestions for selecting Ti3C2Tx as fillers in composites that need fast heat dissipation.

External field alignment of nickel-coated carbon fiber/PDMS composite for biological monitoring with high sensitivity

Abstract Flexible, pressure-sensitive composites can be prepared through the inclusion of electrically conductive particles as functional fillers into an elastomeric polymer matrix, which have been used for the applications of wearable devices for health monitoring and electronic skins. A key challenge associated with these composites is developing anisotropic pressure sensitivity while retaining their flexibility (or low filler content). Herein, we demonstrate a simple and scalable method for aligning anisotropic nickel-coated carbon fibers (NiCF) along with the thickness direction of a polymer matrix by applying a magnetic field. The aligning mechanisms and kinetics of NiCF in the polydimethylsiloxane (PDMS) precursor are revealed by in situ optical microscopy images while a magnetic field is applied. The aligned nickel-coated carbon fibers in the polymer effectively endow the composite films excellent pressure-sensitive performance. The pressure sensitivity of NiCF/PDMS composite films has been systematically studied and can be used for biological monitoring. We believe that this magnetic field assisted processing strategy provides a promising material solution for manufacturing fiber embedded polymer composites with enhanced pressure sensitivity, which is essential for future wearable health monitoring electronics and electronic skin.

Thermal, Magnetic and Electrical Properties of PMMA Nanocomposites with Manganese and Zinc Ferrite Nanoparticles and Their Functionalization

AbstractManganese (MnFe2O4) and zinc (ZnFe2O4) ferrite nanoparticles were synthesized by the combustion method. Furthermore, the modification of these particles with a silane compound was performed. Thus, the particles produced were analyzed for morphology using Scanning electron microscopy (SEM), thermal stability, and composition assisted by Thermogravimetric analysis (TGA). It is noteworthy that the present work used an unprecedented Far‐Fourier‐transform infrared spectroscopy (Far‐FTIR) technique to differentiate the types of ferrites and their surface functionalization, as it is a simpler, more efficient, and high‐resolution method. It is worth mentioning that there are few comparative studies of zinc and manganese ferrites in the literature, much less distinguishing these ferrites simply and efficiently. In addition, there is also a lack of scientific knowledge about its chemical functionalization as compatibilization, especially silanization. Novel PMMA nanocomposites were prepared with the different synthesized particles in the contents from 0.1 % to 1.0 wt.% by the in situ polymerization technique. The nanocomposites were characterized by the analysis of SEM, TGA, Differential scanning calorimetry (DSC), and FTIR mainly by their morphology, thermal resistance, glass transition temperature, proving the chemical interactions, electrical conductivity, capacitance, and dielectric constant. Furthermore, it was evidenced that, in addition to the improvements in thermal, electrical, and interface properties, the produced nanocomposites showed excellent electromagnetic shielding properties even at low filler contents. It is noteworthy that the capacitance increases 63 % for the composite with 1.0 % zinc ferrite and 43 % for manganese ferrite. Also, the electromagnetic absorption results proved that even the low filler contents tested in this work, up to 1.0 %, presented an excellent potential for applying as electromagnetic shielding materials, reaching up to 70 % attenuation with the use of zinc ferrite. Both ferrites showed excellent results, even superior to those found in the literature for other particles with the same purposes, and still needed a lower content to achieve excellent results.

Tuning magnetorheological functional response of thermoplastic elastomers by varying soft‐magnetic nanofillers

AbstractMagnetorheological elastomers (MREs) are increasingly demanded based on their ability to modify their mechanical properties under an applied magnetic field, applications ranging from active control in industrial processes to biomedicine. Those materials are based on a polymer phase and magnetic fillers. This work reports on the evaluation of the effect of the magnetic filler characteristics on the physical–chemical and functional performance of MREs. Composites have been produced with 20 wt% concentration of six different magnetic fillers: CoFe2O4, Fe3O4, Co, Ni, and Ni80Fe17Mo3 (Permalloy) in a SEBS matrix. Elastic modulus increases from 0.7 MPa for the pristine polymer to a maximum value of 1.8 MPa for the sample with Fe3O4. The highest saturation magnetization being obtained for the composite containing magnetite, with 17.8 A m2 kg−1. The filler size, saturation magnetization and coercivity all have significant impact on the magnetorheological (MR) effect. The highest MR effect is achieved when using Fe3O4 nanoparticles (17%), followed by Co (16%), Ni (14%), CoFe2O4 (11%), and finally Permalloy (8%). For the Fe3O4@SEBS composite, the MR response is among the largest reported in the literature but with a much lower filler content (6 vol% versus more than 20 vol%), with a positive effect on processability and integration into devices.

Facile Fabrication of Highly Sensitive Thermoplastic Polyurethane Sensors with Surface- and Interface-Impregnated 3D Conductive Networks.

This research aims to develop a practical, scalable, and highly conductive flexible 3D printed piezoresistive sensor with low filler content. Here, we introduced a fused deposition modeling 3D printing combined in situ spray-coating technique to develop a conductive sensor in a single shot. The graphene suspension is sprayed over each layer during the 3D printing of the sensor, which helps develop a conductive network on the surface and at the interface of the printed system. Graphene deposited on the overall surface is often affected by nanoparticle delamination and loses its function over time. To avoid this, the prepared samples are subjected to foaming. The foaming process created a low-mass-density sensor by forming a microcellular structure, and the surface-deposited graphene is embedded well on the TPU surface. The method followed in this work reveals a stable and connected conduction path with excellent electrical resistance and resistance against harsh conditions (exposure to organic solvents). Besides, the compression sensor withstood its sensitivity over a severe compressive strain of 80% and showed a GF of 1.82 and a sensitivity of 2.316 kPa-1. The conductive network path varied based on the infill pattern, affecting its electrical sensitivity. The wiggle pattern shows good resistance; under stretching, the pattern generated a higher current and showed a delayed conductive path disconnection than other patterns. Thus, the embedded graphene/TPU conductive sensors show good stability and promising sensitivity. Furthermore, the developed sensor is used to monitor human motion and actions.

STUDIES ON THE THERMODYNAMIC PROPERTIES OF NATURAL RUBBER COMPOSITES FILLED WITH CLAY AND CORN COB

The mechanical properties of materials such as natural rubber composites determine their usefulness as engineering or biological materials. The thermodynamic properties of natural rubber composites filled with clay and corn cob at varying volume fraction of filler were studied with a view of relating and comparing thermodynamic parameters (ΔG, ΔH and ΔS) to mechanical properties (Young’s modulus, tensile strength, elongation at break, etc) of natural rubber composites. The rubber composites were prepared using a standard compounding recipe. The tension observed for each rubber composite as a result of changes in temperature was used in evaluating thermodynamic parameters via Arrhenius equation and plot. These properties have been evaluated by measuring the thermodynamic parameters of natural rubber composites compounded with varying percent volume fractions (5% - 25%) of two fillers- clay and corn cob. The results indicated that the maximum values of ΔG and ΔH was obtained for corn cob filled composites at 10% volume fraction, while the optimal values of ΔS for the same composites was found to be at 5% and 25% volume fraction. At lower filler concentration (5 – 17.5%), corn cob filled composites were observed to have higher modulus than clay filled rubber composites, while at these concentration ranges, clay was found to impact higher tensile strength to natural rubber than corn cob filler.

Numerical simulation of plate-like particle orientation in injection molding

This study developed a method for predicting the orientation of plate-like particles within an injection-molded product at low filler content. We derived a numerical model that describes the motion of a plate-like particle and combined it with a mold-filling simulation to calculate the motion of individual flakes during molding. To validate the simulation results, a plaque was injection-molded with polypropylene and 2 wt% glass flakes. X-ray micro-computed tomography analysis was then employed to obtain the orientation (the normal vector) for each flake. The simulation reproduced the through-thickness orientation within the plaque by using a corrected flake aspect ratio. Also, numerical investigation revealed that the orientation is little affected by the in-plane flake shape if the aspect ratio remains the same. A useful application of the simulation will be the prediction of appearance defects caused by the flake orientation misalignment that occur in metallic-looking products molded using thermoplastics containing metallic-flake pigments.

Characterization of moisture uptake and diffusion mechanisms in particle-filled composites

This study investigates moisture uptake and diffusion mechanisms in thermoset particle-filled composites for anchor applications. Two epoxy-based with low inorganic filler content and one vinyl ester-based with high inorganic filler content were studied. Material characterization revealed particle size distribution, particle density, the occurrence of pores, and filler composition. Moisture diffusion was monitored at different temperatures, different relative humidities, and in water immersion for up to 540 days. Based on these results a sorption isotherm, temperature dependencies, and diffusion paths could be determined. A phenomenological hybrid-isotherm, consisting of a combination of Henry's linear isotherm and Type III isotherm, was applied to describe the effect of different fillers on equilibrium moisture uptake. Fickian diffusion was observed for all composites with temperature-dependent Arrhenius relation. These observations allowed us to suggest three diffusion paths: through the polymer matrix, on the matrix-filler interfaces, and through matrix and fillers simultaneously.

Improved mechanical, thermal conductivity and low heat build-up properties of natural rubber composites with nano-sulfur modified graphene oxide/silicon carbide

It is still a bottleneck to simultaneously attain enhanced mechanical properties, thermal conductivity and low heat build-up properties for graphene-rubber composites obtained by conventional fabrication processes. The critical elements to enhance the comprehensive performance of rubber include excellent dispersion and the interaction of filler and matrix. In this work, the increased filler structure degree with point-surface structured SiC/GO (SG) and the strong interface modified with nano-sulfur synergistically improve the dispersibility and interfacial interaction, which effectively achieves excellent integrated performance at low filler content. More importantly, nano-sulfur not only acts as a modifier to improve interfacial compatibility, but also has a vulcanization function that enables SG and natural rubber (NR) molecular chains to form a uniformly distributed cross-linked network structure. Consequently, only when 4 phr of SiC/GO-S (SG-S) filler was added to NR, the tensile strength, thermal conductivity and low heat generation properties are higher than those of NR/GO rubber by 22.5%, 21.2% and 8.3%. Therefore, this work may open new horizons for the development of green tire.

Improved the dielectric properties of thermoplastic polyurethane elastomer filled with MXene nanosheets and BaTiO3 nanofibers

To achieve high deformation under a low electric field intensity is still a big challenge for the dielectric elastomers (DE) potentially used in artificial electronic skin and artificial muscles. Herein, poly-dopamine (PDA) modified 1D barium titanate (BT@PDA) nanofibers and 2D MXene nanosheets with high aspect ratio and large dipole moment were fabricated, and introduced into TPU elastomers. Results showed that the interfacial polarization and micro-capacitor structure formed by MXene sheets lead to the high dielectric constant, and high dielectric loss of MXene/TPU composites with low modulus. The interfacial polarization caused by BT@PDA nanofibers resulting in high dielectric constant and low dielectric loss of BT@PDA/TPU composites with high modulus. Combing the advantages of the two fillers, the MXene/BT@PDA/TPU composites showed high dielectric constant, low dielectric loss, low modulus. The electrical sensitivity factor of 0.5 wt% MXene/5 wt% BT@PDA/TPU composite (11.38) was much higher than the sum of that of 0.5 wt% MXene/TPU (1.73) and 5 wt% BT@PDA/TPU (4.35) composites at a low filler content, showing the 0.5 wt% MXene/5 wt% BT@PDA/TPU dielectric composite had a large deformation under a low electric field. This work can provide an effect strategy to design DE nanocomposites with good deformation performance.

Adhesive wear behaviour of surface modified bamboo filler reinforced polymer composite under different contact condition

ABSTRACT An experimental study has been conducted to evaluate the adhesive wear behavior of bamboo filler-reinforced polymer composite. Bamboo has the significant attention of investigators due to its benefits over human-made fibers. The bamboo fillers’ surface is treated by the alkali treatment process and the composite is prepared with a variation of micro bamboo particle support (i.e. 0, 2.5, 5, 7.5, 10, and 12.5%). The study of tribological characterization is explored for dry, wet, and heated sliding contact state using the pin-on-disk tribomachine counter to a stainless steel disc. Modified bamboo filler composite exhibited better interaction between filler and matrix, which improve the wear resistance capacity of the composite. From the experimental result it is found that specific wear rate and coefficient of friction is lesser in wet condition compared to dry and heated state conditions. Moreover, lower filler content offered enhanced wear performance related to the higher filler content composite. In case of dry sliding contact, debonding and plastic deformation are witnessed on the composite surfaces. However, the worn regions are minimal under wet state condition. Further, in case of the heated state, a thin layer created on the exterior of composite which safeguards the surface from further worn.

Porous N-doped Ni@SiO2/graphene network: Three-dimensional hierarchical architecture for strong and broad electromagnetic wave absorption

Electromagnetic wave absorber is critical for reducing increasingly serious electromagnetic wave pollution, however, the development of lightweight and broadband microwave absorbers remains a pressing challenge. We report here the rational design and synthesis of N-doped [email protected]2/graphene composite constructed from 3D interconnected porous graphene network and [email protected]2 core-shell architecture, which fulfills lightweight and broadband requirements while exhibiting highly efficient electromagnetic wave absorption. The porous graphene network, functioning both as lightweight support and dielectric mediator, was synthesized via NaCl template-assisted high-temperature calcination method. Upon uniformly attached with core-shell [email protected]2 on the surface, the resulting abundant heterogeneous interfaces constructed by graphene-Ni and Ni-SiO2 strongly reinforce polarization loss. The presence of low dielectric SiO2 allows facile tuning of the complex permittivity of ternary composite by adjusting coating thickness to balance the attenuation ability and impedance matching. Moreover, further N-doping of graphene assists in the optimization of dielectric loss ability. Taking account of the advantages arising from the porous hierarchical architecture, multiple absorption centers and diverse interfaces, the lightweight composite exhibits an ultra-strong reflection loss (RL) value of - 71.13 dB at 13.76 GHz with a thickness of 2.46 mm and broad effective absorption bandwidth of 7.04 GHz at a low filler content of 15 wt.%. More importantly, the effective absorption range covers 13.28 GHz (4.72–18 GHz) with the optimized thickness of 1.6–5 mm, representing 83% of the whole range of frequencies. Our results demonstrate that the novel 3D porous N-doped [email protected]2/graphene network with hierarchical architecture is a promising candidate for high-performance electromagnetic wave absorption.