Electromagnetic Interference Shielding Capability Research Articles

Ti3C2Tx Electromagnetic Shielding Performance: Investigating Environmental Influences and Structural Changes

AbstractMXenes, a promising family of 2D transition metal carbides/nitrides, are renowned for their exceptional electronic conductivity and mechanical stability, establishing them as highly desirable candidates for advanced electromagnetic interference (EMI) shielding material. Despite these advantages, challenges persist in optimizing MXene synthesis methods and improving their oxidation resistance. Surface defects on MXenes significantly impact their electronic properties, impeding charge transport and catalyzing the oxidation process. In this study, a novel synthesis protocol derived from the conventional, minimally invasive layer delamination (MILD) method, is presented. Two additional steps are introduced aiming at enhancing process yield, addressing a crucial issue as conventional methods often yield high‐quality individual MXene flakes but struggle to generate sufficient quantities for bulk material production. This approach successfully yields Ti3C2Tx films with excellent conductivity (3973.72 ±121.31 Scm−1) and an average EMI shielding effectiveness (SE) of 56.09 ± 1.60 dB within the 1.5 to 10 GHz frequency range at 35% relative humidity (RH). Furthermore, this investigation delves into the long‐term oxidation stability of these films under varying RH conditions. These findings underscore the effectiveness of this innovative synthesis approach in elevating both the conductivity and EMI shielding capabilities of MXene materials. This advancement represents a significant step toward harnessing MXenes for practical applications requiring robust EMI shielding solutions. Additionally, insights into long‐term stability offer critical considerations for implementing MXenes in real‐world environments.

Investigation of electromagnetic shielding effectiveness of nano silver coated stainless steels

This paper presents the shielding effectiveness (SE) of various nanosilver-coated stainless steels (201, 304, 316 and 430), using a coaxial transmission line setup with waveguides and a vector network analyzer (VNA) in accordance with ASTM 4935 standards. The conducted experiments revealed excellent SE outcomes, indicating that the silver-coated stainless steel samples exhibited notably superior SE performance compared to their uncoated counterparts. The importance of SE in electromagnetic compatibility (EMC) applications, particularly in minimizing electromagnetic interference (EMI) and safeguarding sensitive electronic devices, is well acknowledged. This study further explored the shielding effectiveness of a novel hybrid material, nano silver (Ag) coated different stainless steels, with a focus on its potential for improved EMI shielding capabilities. Experimental measurements were conducted in the 5G frequency domain.It was found that nanosilver coating increased the SE of stainless steels by between 5 and 12 dB. This enhancement attributed to the incorporation of nanostructured silver particles on the stainless steel surface, which facilitates enhanced reflection of electromagnetic waves, resulting in superior shielding performance. Moreover, this study underlying the mechanisms of SE through various analyses, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). In summary, this research has demonstrated that nano silver coating increases the SE value of materials. This result suggests that all other materials can be used to increase the SE value. The results have implications for advancing electromagnetic shielding technologies and promoting the development of robust EMI shielding solutions in various industrial applications where effective shielding is of paramount importance.

An overpressure monitoring system based on PVDF integrated Electronic sensor with enhanced noise attenuation capability

The measurement of shockwave overpressure is of great significance for the safe use of explosives. The traditional overpressure monitoring systems are based on Integrated Electronics Piezo-Electric (IEPE) ceramic sensors. However, the brittleness of piezoelectric ceramic limits the application of overpressure monitoring system in high impact overpressure testing. Herein, a novel overpressure monitoring system based on Integrated Electronic Poly (vinylidene fluoride) (PVDF) (PFIE) sensor with electromagnetic interference shielding capability and parasitic vibration noise elimination function was designed for intense overpressure acquiring. PVDF, as a polymer, can endure much higher impact pressures compared to piezoelectric ceramics. However, its larger internal resistance makes it more prone to electromagnetic interference. To address this, an electromagnetic shielding structure was designed, incorporating an impedance matching circuit that effectively reduces the sensor's output impedance. Additionally, to mitigate excessive vibration noise during overpressure testing, the differential noise reduction technique has been implemented. Both the laboratory testing and the real blast testing with 10 kg trinitrotoluene were performed to validate the PFIE overpressure monitoring system. The result shows that the electromagnetic noise suppression ability of the PFIE overpressure sensors developed for the monitoring system was improved by 45 dB, and the parasitic vibration noise could be attenuated from 30 % to 1 %, what’s more the RMS errors of the overpressure dynamic parameters obtained by the monitoring system were below 10 %. This work has successfully addressed the noise sensitivity issue inherent in PVDF when used as a pressure sensor, capitalizing on its robust impact resistance. This approach has provided a viable solution for measuring overpressure in scenarios involving intense shock pressures, leveraging the strengths of PVDF in such demanding applications.

Regulating synergistic micro-nano pore structure of CNT sponge to control EMI shielding performance

The aggregation in high-content carbon nanotube reinforced silica carbide composites (CNT/SiC) imposed constraints for further large-scale industrial applications. This study established a synergistic micro-nano pore structure by assembling CNT bundles to fabricate the CNT sponge preform, and then the SiC matrix was in-situ deposited by chemical vapor infiltration method, which facilitates composites with high density and exceptional properties. The pore size distribution and pore area can be regulated by simply adjusting the compression ratios (CRs) of the as-assembled CNT sponge. Samples with CR of 50 % exhibited noteworthy densification, significantly reduced porosity, and a remarkable 163.54 % extra increase in compression strength compared to uncompressed ones. Additionally, the CNT/SiC composites displayed excellent oxidation resistance and demonstrated improved electromagnetic interference (EMI) shielding performance, which exhibited a substantial increase with higher CRs. These findings underscore the significance of employing appropriate multi-level porosity in CNT preforms to fabricate advanced ceramic matrix composites with superior EMI shielding capabilities.

Controllable proton-reservoir ordered gel towards reversible switching and reliable electromagnetic interference shielding.

Smart and dynamic electromagnetic interference (EMI) shielding materials possess a remarkable capacity to modify their EMI shielding abilities, rendering them invaluable in various civil and military applications. However, the present response mechanism of switch-type EMI shielding materials is slightly restricted, as it primarily depends on continuous pressure induction, thereby resulting in concerns regarding their durability and reliability. Herein, for the first time, we demonstrate a novel method for achieving solvent-responsive, reversible switching, and robust EMI shielding capabilities using a controlled proton-reservoir ordered gel. The gel contains polyaniline (PANI) and sodium alginate (SA). Initially, SA acts as a proton reservoir for PANI in an aqueous system, enhancing the doping level of PANI and improving its electrical conductivity. Additionally, PANI and SA chains respond to diverse polar solvents, such as water, acetonitrile, ethanol, n-hexane, and air, inducing distinct conformations that affect the degree of PANI conjugation and electron migration along the chains. This process is reversible and non-destructive to the polymer chain, ensuring the effective and uncompromised performance of the EMI shielding switch. We can achieve precise and reversible tuning (on/off) of EMI shielding with different effectiveness levels by manipulating the solvents within the framework. This work opens a new solvent-stimuli avenue for the development of EMI shielding materials with reliable and intelligent on/off switching capabilities.

Thermally tunable ethanol impregnated PDMS/CoZTO/SWCNT composite architecture for smart electromagnetic shielding

Shape memory elastomer composites with externally stimulated shielding capability are greatly sought to protect high-end artificial intelligence-based electrical and telecommunication devices in the military, aerospace, robotics, etc., from electromagnetic interference (EMI). However, the fabrication of such composites integrated with externally responsive green EMI shielding capabilities is promising but greatly challenging. Herein, ethanol (thermally active phase) mixed polydimethylsiloxane (PDMS)/single wall carbon nanotube (SWCNT)/cobalt doped zinc tin oxide (CoZTO) hybrid composite with an active guest method was devised. This design strategy explores how the thermally controlled liquid-gas phase transition led microstructural modifications regulate the macroscopic shielding features like absorption enhancement and reflection minimization. The composite adapts the 72.18 % volumetric actuation by liquid-to-vapor phase transition of ethanol at 80 °C, promoting the total EMI shielding value up to 48.77 dB from 18.4 dB at 20 GHz due to microstructure induced electromagnetic modifications. Additionally, a green index of 7.2 confirms the absorption dominance over reflection shielding in the studied composite. Furthermore, ethanol-generated foamed architecture of composite offers pressure-sensitive on-off shielding tunability, which accounts for the potential use in manufacturing advanced RF switches.

Temperature-stimulated composite foams for reversibly switching microwave absorption towards electromagnetic interference shielding capability

Currently, electromagnetic interference (EMI) shielding and microwave absorption are two important means to alleviate the increasingly severe electromagnetic (EM) pollution. However, the application areas of EMI shielding and microwave absorption are quite different, so integrating these two capabilities in the same material is a great challenge. Herein, multiple-scale polyurethane (PU) composite foams (CFs) assisted by tadpole-like carbon nanotube (CNT)@Fe3O4 nanocomposites were designed by a facile solvothermal and self-foaming method. By adjusting the CNT@Fe3O4 loadings and ambient temperatures, the EM parameters and interface impedance matching of PU/CNT@Fe3O4 CFs could be optimized, thus realizing the coexistence of EMI shielding and microwave absorption inside one same material. The resulting CF exhibited an effective minimum reflection loss (RLmin) of −41.9 dB and EMI shielding effectiveness (SE) of ∼20 dB. Furthermore, the elevated temperatures within a range of −20-60 °C would stimulate the transformation of individual CF from microwave absorption towards EMI shielding capability and vice versa. This work will promote the development of intelligent EM compatible devices in the field of optional EM protection.

Bio-inspired smart composite architecture for thermally tunable green EMI shielding

Bio-imitating externally stimulated smart flexible composites are highly sought after for the innovations of next-generation advanced artificial intelligence-based electronic technologies, such as robots, defense, wireless and satellite communications, etc., to protect from electromagnetic interference (EMI). Herein, eco-friendly active guest in passive host composite of polydimethylsiloxane (PDMS)/silver-doped zinc stannate (SZTO)/single wall carbon nanotubes (SWCNT) containing an active fluid (water) was fabricated for thermally tuned smart EMI shielding. This soft robust composite with ultra-low fillers integrates temperature induced outstanding smart EMI shielding capabilities in the 14.5 GHz to 20 GHz frequency band. The water serves as a temperature responsive active phase, enhancing the radiation-shielding performance up to 50.4 dB at 100 °C. Additionally, the composite exhibits a green index greater than six, indicating an extraordinary absorption-dominated green shielding response. Hence, this design strategy enables the development of externally stimulated multifunctional autonomous composite architecture for smart green EMI shielding.

High-Performance Transparent Ultrabroadband Electromagnetic Radiation Shielding from Microwave toward Terahertz.

In the era of fifth-generation networks and Internet-of-Things, the use of multiband electromagnetic radiation shielding is highly desirable for next-generation electronic devices. Herein, we report a systematic exploration of optoelectronic behaviors of ultrathin-silver-based shielding prototype (USP) film structures at the nanometer scale, unlocking the transparent ultrabroadband electromagnetic interference (EMI) shielding from microwave to terahertz frequencies. A theoretical model is proposed to optimize USP structures to achieve increased transparency, whereby optical antireflection resonances are introduced in dielectrics in conjunction with remarkable EMI shielding capability. USP can realize a state-of-the-art effective electromagnetic radiation shielding bandwidth with measured frequencies from 8 GHz up to 2 THz. Experimental results show that a basic USP (dAg = 10 nm) offers an average shielding efficiency of ∼27.5 dB from the X- to Ka-bands (8-40 GHz) and maintains a stable shielding performance of ∼22.6 dB across a broad range of 0.5-2 THz, with a measured optical transmittance of ∼95.2%. This extraordinary performance of ultrathin-silver-based film structures provides a new ultrabroadband EMI shielding paradigm for potential applications in next-generation electronics.

A novel multisource energy harvester with enhanced thermal conductivity for efficient energy harvesting and superior EMI shielding

With the rapid growth of industries, renewable energy sources like wind and solar have emerged as prominent alternatives. However, their inherent intermittency demands the development of efficient energy harvester technologies. Conventional energy harvesters are limited to capturing a single energy type, resulting in compromised storage capabilities. Moreover, the detrimental effects of electromagnetic interference (EMI) on equipment necessitate immediate attention. To address these challenges, we present the development of a novel phase change composite, CMW@PEG, which possesses remarkable enhancements in thermal conductivity (1.26 W/m∙K), electrical conductivity (71.9 S/cm), and UV absorption capacity (close to 1). Notably, this composite exhibits an outstanding EMI shielding capability of 49.36 dB, safeguarding equipment operations effectively. Furthermore, it showcases impressive solar-thermal (87.9 %) and electric-thermal (93.3 %) conversion efficiencies. The unique properties of CMW@PEG offer a pioneering strategy for harnessing and utilizing renewable energy efficiently and hold tremendous promise in advancing the sustainable energy landscape.

Influence of carbon fiber nickel electroplating on the electromagnetic interference shielding and mechanical properties of carbon fiber reinforced polyamide 6 composites

AbstractThis article investigates the use of nickel electroplated carbon fiber (Ni‐CF) fabric to enhance the electromagnetic interference (EMI) shielding capability of carbon fiber reinforced thermoplastics (CFRTs), particularly for automotive and aerospace applications. The study examines the influence of nickel electroplating parameters of carbon fiber on the morphologies of carbon fiber fabrics. Ni‐CF reinforced polyamide 6 (Ni‐CF/PA 6) was prepared by the film‐stacking method. The flexural properties analysis demonstrates a 21.1% increase in flexural strength for Ni‐CF/PA 6 composites compared to as‐received carbon fiber reinforced PA 6 (CF/PA 6) composites. Additionally, the introduction of nickel layer significantly improves the EMI shielding efficiency of CF/PA 6 composites, with the average shielding efficiency increasing from 23.5 to 31.6 dB within the X‐band and Ku‐band frequency ranges. Scanning electron microscope (SEM) analysis confirms that the nickel layer enhances the interfacial bonding between the PA 6 matrix and the Ni‐CF, which is attributed to the micro cone‐shaped structures of the nickel layer. Overall, the electroplating method effectively modifies the carbon fiber surface, resulting in composite laminates with enhanced mechanical properties and superior EMI shielding efficiency. These findings provide valuable insights for the development of advanced carbon fiber reinforced composites with improved functionalities in various applications.Highlights The electroplating method is used to process the nickel electroplated carbon fiber fabrics. The introduction of micro cone‐shaped structure nickel on the fiber surface by electroplating provides the mechanical interlocking between carbon fiber and matrix. The nickel electroplated carbon fiber can significantly increase electromagnetic interference shielding capability of carbon fiber reinforced thermoplastic composites.

An All‐Stretchable, Ultraviolet Protective, and Electromagnetic‐Interference‐Free E‐Textile

AbstractFlexible and skin‐mountable electronics have drawn tremendous research attention with the booming of smart medical systems and wearing technologies, however, their environmental adaptability to electromagnetic and solar radiation has long been neglected. Herein, a novel health monitoring e‐textile with robust ultraviolet (UV) protecting and strong electromagnetic interference (EMI) shielding performance is rationally developed on an ultraelastic and bilayered nonwoven textile. Via the respective incorporation of silver flake‐modified liquid metal (AgLM) and silver nanoparticles (AgNPs) on each side of a permeable substrate, a Janus sensing layer with electrophysiological monitoring function, Joule heating ability, and excellent EMI shielding capability (up to 38.5 dB in X band) is first fabricated. Elastic microfibers embedded with sensitive photochromic microcapsules are then in situ assembled on the bioelectric‐sensing layer, achieving a bilayered e‐textile with a reversible UV‐chromic property and an extraordinary UV protection factor (UPF) of 335.56. The developed all‐stretchable and UV‐EMI proof e‐textile is utilized as a safe and comfortable on‐skin electronic to provide point‐of‐care health regulation under complex UV/EMI radiative environments. Specifically, stable Joule heating performance and accurate monitoring of electrocardiogram (ECG) and surface electromyography (sEMG) are simultaneously obtained, demonstrating promising applications in multifunctional and robust wearing electronics.

Eco-Friendly Silver Nanoparticles/Chitosan/Poly(vinyl alcohol) Composites Exhibit Remarkable EMI Shielding Capabilities and Outstanding Thermal Conductivities.

The integration and miniaturization of contemporary electronics have led to significant challenges in dealing with electromagnetic (EM) radiation and heat accumulation. Despite these issues, achieving high thermal conductivity (TC) and electromagnetic interference (EMI) shielding effectiveness (SE) in polymer composite films remains an exceptionally difficult task. In this work, we used a straightforward in situ reduction process and a vacuum-drying method to successfully prepare a flexible Ag NPs/chitosan (CS)/PVA nanocomposite with three-dimensional (3D) conductive and thermally conductive network architectures. The 3D silver pathways formed by attaching to the chitosan fibers endow the material with simultaneous exceptional TC and EMI capabilities. At a silver concentration of 25 vol %, the TC of Ag NPs/CS/PVA nanocomposites reaches 5.18 W·m-1·K-1, exhibiting an approximately 25 times increase compared to CS/PVA composites. The electromagnetic shielding performance of 78.5 dB significantly outperforms the specifications of standard commercial EMI shielding applications by a significant margin. Additionally, Ag NPs/CS/PVA nanocomposites have greatly benefited from microwave absorption (SEA), effectively impeding the transmission of EM waves and reducing the reflected secondary EM wave pollution. Meanwhile, the composite material still maintains good mechanical properties and bendability. This endeavor helped develop malleable and durable composites that possess superior EMI shielding capabilities and intriguing heat dissipation properties using innovative design and fabrication methods.

Slippery Graphene-Bridging Liquid Metal Layered Heterostructure Nanocomposite for Stable High-Performance Electromagnetic Interference Shielding.

Gallium-based liquid metal (LM) with intriguing high electrical conductivity and room-temperature fluidity has attracted substantial attention for its potential application in flexible electromagnetic interference (EMI) shielding. However, the EMI shielding performance of the existing LM-based composites is unsatisfying due to the irreconcilable contradiction between high EMI shielding efficiency (SE) and low thickness. In addition, the research on environmentally stable EMI shielding material has become an urgent need due to the increasingly sophisticated application scenarios. Herein, we prepared a reduced graphene oxide (rGO) bridging LM layered heterostructure nanocomposite with the liquid-infused slippery surface (S-rGO/LM), which exhibits an ultrahigh X-band EMI SE of 80 dB at a mere internal thickness of 33 μm, and an extremely high value of 100 dB at an internal thickness of 67 μm. More significantly, protected by the ultrathin (2 μm) yet effective slippery surface, the S-rGO/LM film exhibits exceptional EMI shielding stability (EMI SE stays above 70 dB) after enduring various harsh conditions (harsh chemical environments, extreme operating temperatures, and severe mechanical wearing). Moreover, the S-rGO/LM film also demonstrates satisfying photothermal behavior and excellent Joule heating performance (surface temperature of 179 °C at 1.75 V, thermal response <10 s), which endows it with the capability of anti-icing/de-icing. This work proposes a way to construct an LM-based nanocomposite with reliable high-performance EMI shielding capability, which shows great potential for applications in wearable devices, defense, and aeronautics and astronautics.

Sandwich-structured Ti3C2Tx-MXene/reduced-graphene-oxide composite membranes for high-performance electromagnetic interference and infrared shielding

The electromagnetic interference (EMI) shielding abilities of MXene-based conductive nanocomposites are promising for ensuring the steady operation of electronic equipment and protecting people from electromagnetic radiation. The development of comprehensive membranes that satisfy all the essential requirements of excellent EMI shielding and infrared (IR) stealth performance remains a significant issue, despite the high EMI shielding capabilities of MXene-based composite membranes. Here, we report a sandwich-structured Ti3C2Tx-MXene/reduced-graphene-oxide (MrG) membrane with high conductivities and abundant interior blowholes for high-performance EMI shielding and IR stealth. Taking advantage of the continuously conductive routes and distinctive porous structures, an 18-μm-thickness MrG membrane shows a high EMI shielding efficiency (EMI SE) of 89.1dB and a satisfactory absolute EMI SE (SSE/t) of up to 55282.8 dB⋅cm2⋅g−1, which is the best result for MXene-based nanocomposites with similar thickness. Moreover, the MrG membrane also exhibits superior thermal camouflage ability for objects in low-temperature circumstances (like winter) and high-temperature cases (like summer), demonstrating the great promise as high-performance EMI shielding membranes for IR stealth, security protection, and counter-surveillance.

Electrochemically modulated interaction of MXenes with microwaves.

Dynamic control of electromagnetic wave jamming is a notable technological challenge for protecting electronic devices working at gigahertz frequencies. Foam materials can adjust the reflection and absorption of microwaves, enabling a tunable electromagnetic interference shielding capability, but their thickness of several millimetres hinders their application in integrated electronics. Here we show a method for modulating the reflection and absorption of incident electromagnetic waves using various submicrometre-thick MXene thin films. The reversible tunability of electromagnetic interference shielding effectiveness is realized by electrochemically driven ion intercalation and de-intercalation; this results in charge transfer efficiency with different electrolytes, accompanied by expansion and shrinkage of the MXene layer spacing. We finally demonstrate an irreversible electromagnetic interference shielding alertor through electrochemical oxidation of MXene films. In contrast with static electromagnetic interference shielding, our method offers opportunities to achieve active modulation that can adapt to demanding environments.

Asymmetric multilayered MXene-AgNWs/cellulose nanofiber composite films with antibacterial properties for high-efficiency electromagnetic interference shielding

• Multilayer films containing cellulose nanofiber (CNF) layers, CNF/MXene layers, and CNF/silver nanowires (CNF/AgNWs) layers were fabricated by an efficient and easy-to-use vacuum filtration method. • The effects of different conductive layers order and different number of layers on electromagnetic shielding performance were investigated. • Due to the excellent layered structure, the MXene-AgNWs/cellulose nanofiber composite film exhibits excellent EMI shielding capability at an ultra-thin thickness. • Benefiting from the properties of silver nanowires, the multifunctional shielding composite exhibits excellent antibacterial properties and better environmental adaptability. Flexible, lightweight, robust and versatile properties are essential for the next generation of wearable as well as intelligent electromagnetic interference (EMI) shielding materials. In this work, multilayered films containing cellulose nanofiber (CNF) layers, CNF/MXene layers, and CNF/silver nanowires (CNF/AgNWs) layers were fabricated by an efficient and easy-to-use vacuum filtration method. Compared with a uniformly mixed film, the resultant layered composite films that loaded with a low MXene and AgNWs content exhibit superior mechanical properties with a tensile strength of 137 MPa, a strain at break of 5.7%, excellent EMI shielding effectiveness (EMI SE) of 61.9 dB, and higher EMI SE/t of 20,653 dB cm −1 . This is attributed to the high-performance CNF substrate, the highly efficient layered structures, and extensive hydrogen-bonding interactions. In particular, a high degree of ohmic loss of multiple interfaces and polarization relaxation of local defects, as well as an abundance of terminal groups, favor the loss of electromagnetic waves (EMW) within the material. In addition, the prepared multifunctional layered composite films also show good antibacterial properties. As a result, the obtained new kind of flexible layered structure EMI shielding composite films with excellent EMI shielding performance, and mechanical properties present promising application prospects in the fields of EMI shielding and protection for aerospace, portable, and wearable flexible electronic devices.

Highly dispersed graphene nanoplatelets in polypropylene composites by employing high-shear stress for enhanced dielectric properties and frequency-selective electromagnetic interference shielding capability

Although graphene nanoplatelets (GNPs) are currently receiving significant interest as a filler for polymer composites, the issue of agglomeration is yet to be overcome for their wide applications. Herein, the high-shear extrusion technique was thoroughly investigated to effectively disperse GNPs in a polypropylene (PP) matrix with a content of 3 wt%. The screw rotation speed was controlled in the range of 1000–3000 rpm, which is extremely high corresponding to the shear rate of 733–2199 s−1 that should be compared with 200 rpm and 99 s−1 of a conventional extruder, respectively. As the shear rate increased, the size of GNP agglomerates decreased from several microns to ca. 250 nm. This size reduction resulted in the significant enhancement of dielectric loss, owing to the strong interfacial polarization at the interfaces between the GNPs and PP matrix. Furthermore, frequency-selective characteristics in electromagnetic interference shielding could be controlled in the wide frequency spectrum covering the X- and Ka-bands by adjusting the shear rates providing different aperture sizes specified by the interstitial distances of GNPs. Altogether, the developed GNP/PP nanocomposites and their methodology have remarkable potential as promising solutions for graphene-based polymer composites.

Clipping electron transport and polarization relaxation of Ti3C2Tx based nanocomposites towards multifunction

High-performance multifunctional electromagnetic (EM) materials exhibit great potential for development, and have attracted extensive attention from the scientific field. Generally, the dielectric "genes", including conductive networks, interfaces, and defects, are the pivotal factors that determine their performance. Herein, multifunctional Ti3C2Tx@polyaniline decorated MWCNT (TPMC) nanocomposites, containing generous dielectric "genes", were synthesized via the electrostatic self-assembly method. Thanks to the regulation of internal dielectric "genes", TPMC exhibited a tunable EM wave absorption (EMA) and EM interference (EMI) shielding performance. TPMC achieved a maximum reflection loss (RL) of −54.7 dB and an effective absorption bandwidth (EAB) of nearly 6 GHz at 1.5 mm. Moreover, the complete conductive networks endowed TPMC with a reliable EMI shielding capability. It exhibited a maximum EMI shielding effectiveness (SE) of 34 dB, and meanwhile, displayed an absorption-dominated green shielding performance. Furthermore, owing to the integration of the "genes", TPMC showed a high coulomb efficiency (∼98%) and excellent cycling stability (exceeded 95% retation after 8000 cycles), indicating a great potential as outstanding supercapacitor electrode material. This work provides a promising strategy for controlling the EM pollution and alleviating the energy issues.

Mussel-inspired strategy to construct 3D silver nanoparticle network in flexible phase change composites with excellent thermal energy management and electromagnetic interference shielding capabilities

Nowadays, efficient thermal management and electromagnetic interference shielding as effective measures for maintaining the normal operation of electronic devices are extremely significant. However, composites with both thermal management and electromagnetic interference shielding performance are rarely reported. In this study, a kind of flexible polydopamine (PDA) and silver nanoparticles (AgNPs) wrapped melamine foam (MF) constructed by adopting the mussel-inspired strategy was used to fabricate MPAχ-PEG phase change materials (PCMs) via encapsulating polyethylene glycol (PEG). PDA was selected to enhance the interface bonding between MF and AgNPs due to its strong adhesion based on mussel-inspired surface chemistry. Continuous AgNPs wrapped on skeleton of MF construct the three-dimensional (3D) thermal/electrical-conductive porous network. MPAχ-PEG PCMs exhibit a relatively high phase change enthalpy of 148.9 J/g and a high thermal conductivity enhancement of 1400% in comparison with that of MF-PEG. Moreover, MPAχ-PEG PCMs are provided with electromagnetic interference (EMI) shielding performance with the mean SET of 82.02 dB and electro-to-thermal energy conversion efficiency (86.3% under the voltage of 1.2 V) due to the 3D conductive AgNPs network. Combining the elasticity of MPAχ foams and the phase change feature of PEG, the MPAχ-PEG PCMs show good solar-induced shape memory performance. The flexible PCMs could avoid the sharp temperature increase of smartphone by the solid-liquid phase change process of PEG. Therefore, this study provides a promising strategy to prepare flexible PCMs, which can achieve various forms of energy conversion, as well as thermal management and EMI shielding performance, can definitely broaden their application prospect in electronic devices.