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Carbon fiber composites capable of electrical heating, temperature sensing, and electromagnetic interference (EMI) shielding are highly desirable in the field of aerospace. To enhance the electrical heating and EMI shielding performance, graphite oxide (GO) and reduced graphite oxide (RGO) was coated on the surface of carbon fiber fabric, respectively. Followed by solidifying through vacuum-assisted resin transfer molding (VARTM), pure carbon fiber reinforced resin-based composite (CF/EP composites), surface modified carbon fiber reinforced resin-based composites by GO (GO@CF/EP composites) and RGO (RGO@CF/EP composites) were prepared. GO@CF/EP composites give excellent electrothermal properties (the temperature can reach 102 °C under 0.2 A applied current within a fast-responding time of 60 s), and the storage modulus can reach 17,000 MPa. The RGO@CF/EP composite provides an EMI shielding efficiency (SE) of ~ 95 dB at a low thickness of 4 mm. In addition, the linear relation between resistance and temperature of these composite is provided, and the TCR of GO@CF/EP, RGO@CF/EP and CF/EP composites are − 0.57%/ °C, − 0.44%/ °C, and − 0.49%/ °C in a range of 20–100 °C with a resistance variation of 44.9−55.4%. In addition, the interface resistance is provided by a qualitative decoupling analysis method, which account for 16%, 2%, and 29% of the total resistance. These results and methods can propose useful references for carbon-based composite heating devices, carbon-based microwave blockers, sensors, and other technical methods. [ABSTRACT FROM AUTHOR]

Planar frequency selective surface (FSS) fabrics with grids, strips or patches by simple methods of patching, embroidery, clipping and carving were fabricated. The periodic structures, laminated structures, processing method and materials pertaining to the electromagnetic shielding behaviors were investigated. Firstly, equivalent circuit and electromagnetic (EM) shielding behavior of basic frequency selective structure units and complex fretwork structure were provided, involving the decoupling of complex fretwork structure. In addition, various laminating structures of SPs and SGs were determined, one of superposition of SPs and SGs provides a SE peak of 40.2 dB (average SE of 25.1 dB in the whole frequency domain), the other presents a SE peak of 27.1 dB (average SE of 19.1 dB in the whole frequency regime). Furthermore, tunable selective electromagnetic shielding by a simple mechanical way was provided, which can realize a tunable SE peak varying from 730 MHz to 1580 MHz. This work might provide a perspective for the assemble and analytical approximation of FSS fabrics for scientists and engineers in this cross-disciplinary field. [ABSTRACT FROM AUTHOR]

In this paper, to determine the impact of carbon fiber orientation and interweaving on electromagnetic interference (EMI) shielding behaviors, anisotropic and isotropic samples were developed by conductive/dielectric weaving of spatially distributed carbon fiber and glass fiber. Effortless and cost-effective, the electromagnetic shielding efficiency (SE) was up to 42 dB and the SE/thickness) was 41 dB/mm, which had apparent polarization selection characteristics. In addition, the angle (θ) sensitivity for the SE in transverse electric and transverse magnetic polarization modes was given in detail. SE was generally proportional to θ. Moreover, the fingerprint-like radar chart of anisotropic carbon hybrid woven fabrics in the X-band was performed, which makes polarization selection characteristics more intuitive. This paper presented an easy and effective route for assembling hybrid carbon fiber fabrics with high EMI shielding performance, which offers a clear perspective on the simulation and study of carbon fiber electromagnetic properties. [ABSTRACT FROM AUTHOR]

The integration of high conductive networks and textiles has become a favorable technical route to fulfill the objectives of wearable electronics. Herein, high stretchable and recoverable PET fabric coated with a layer of silver nanowire network by a simple and scalable polyol-method is provided. The electrothermal performance, resistance temperature-sensitivity, electromagnetic shielding performance, strain sensing, and washability of silver nanowire (AgNWs)/PET fabrics with different coating times were performed. The conductivity of the fabric coated AgNWs of 2.8 mg/cm2 is as high as 175 S/m, the EMI shielding effectiveness is 37 dB, and it gives a highly sensitive strain response to human movement (gauge factor of −6.16 under 10% strain) and an underwater oil repellent angle of 125°. The heating temperature can reach above 100°C within 27 s under an applied current of 0.10 A. In addition, an excellent linearity of the resistance temperature-sensitive behavior for AgNWs/PET fabrics is obtained, and fabric Ag-5 gives a negative temperature coefficient of resistance (TCR) of −0.05%/°C. Knitted fabric with multi-function is obtained by use of silver nanowire coating. This method provides a simple, low-cost and easy-to-scalable process for the production of electronic textiles, such as fabric heater, microwave blocker, sensor, and other technologies. [ABSTRACT FROM AUTHOR]

• Electromagnetic shielding, resistance temperature-sensitive behavior, and interfacial electricity of RGO papers are provided. • The conductivity anisotropy verse temperature and pizeoresistivity of RGO papers at different are characterized. • A simple experimental approach to prepare graphene papers with remarkable electromagnetic shielding performance is provided. • A qualitative decoupling analysis method is provided for the study and analysis of interfacial electricity for RGO papers. Electromagnetic shielding behavior, resistance temperature-sensitive behavior, interfacial electricity, and their variations with heating treatment of the reduced graphene oxide (RGO) paper are of concern. Herein, self-assembling RGO papers were prepared by solution-phase deposition method. An electromagnetic shielding efficiency (EMSE) of 64 dB shielding (corresponding to a SE/Grammage of 7032 dB/(g/cm2)) covering X-band (8–12 GHz) were obtained. In addition, resistance temperature-sensitive behavior of RGO paper is investigated, and equivalent circuit model is established to decouple interface electricity. The relative resistance variations of RGO paper is caused by the temperature, and the value of ∆R/R 0 drops by around 36% when the RGO paper temperature increase from 200 °C to 800 °C. This graphene-based paper provides a simple experimental approach to prepare graphene papers with remarkable electromagnetic shielding performances. More importantly, a qualitative decoupling analysis method is provided for the study and analysis of interfacial electricity. These results and decoupling method can provide useful data and method for carbon-based microwave blockers, sensors and other technologies. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO) and magnetic metal oxide composite papers are high needed in microwave absorption, shielding and rapid electrical heating. Herein, a self-assembled multifunctional RGO/MnFe 2 O 4 paper is effectively prepared by a simple method of solution casting and thermal reduction for electromagnetic shielding, microwave absorption, temperature-sensing, electrothermal de-icing. A fast electrical heating is achieved, a saturation temperature of 100.2 °C can be provided within 15 s at a constant current of 0.35 A. In addition, the composite paper under a thermal reduction temperature of 800 °C gives an electromagnetic shielding efficiency (SE) value of 29 dB at X-band and a reflection loss (RL) of 43.2 dB at 14.1 GHz with a thickness of 3 mm and an effective bandwidth (RL < −10 dB) from 10.5 to 16.2 GHz. More, the contact resistance between the graphene-based paper and electrode is decoupled based on the equivalent circuit model, which is greatly contribute to its higher electrothermal and other electrical performance. And the contact resistance is 19.18 Ω, which accounts for 15% of the total resistance of the RGO/MnFe 2 O 4 composite. This RGO/MnFe 2 O 4 paper can offer great potential for fast electrical heater, high performance microwave absorbing and shielding materials. [Display omitted] • A self-assembled RGO/MnFe 2 O 4 paper is prepared by a simple method of solution casting and thermal reduction. • The performance of electromagnetic shielding, microwave absorption, electrothermal de-icing are investigated carefully. • The process of graphene-based films is relatively simple and can be widely used. • Decoupling based on the equivalent circuit model shows the contact resistance between the graphene-based film and electrode. • This work can provide useful values for high performance microwave absorberand fast electrical heater. [ABSTRACT FROM AUTHOR]