Enhanced X-Band Electromagnetic-Interference Shielding Performance of Layer-Structured Fabric-Supported Polyaniline/Cobalt–Nickel Coatings

Abstract

Despite tremendous efforts, fabrication of lightweight conductive fabrics for high-performance X-band electromagnetic-interference (EMI) shielding remains a daunting technical challenge. We herein report an ingenious and efficient strategy to deposit polyaniline/cobalt-nickel (PANI/Co-Ni) coatings onto lyocell fabrics that involves consecutive steps of in situ polymerization and electroless plating. The PANI-Co-Ni ternary-component system successfully induced a synergistic effect from EM wave-absorption and EM wave-reflection and, moreover, upgraded the match level between magnetic loss and dielectric loss. By the judicious control of polymerization cycles and plating time, low-weight fabric-supported PANI/Co-Ni composites (with PANI and Co-Ni loading of 2.86 and 3.99 mg·cm, respectively) were prepared, which displayed relatively high EMI shielding effectiveness (SE) (33.95-46.22 dB) when compared to their single peers (PANI-coated fabric and Co-Ni-coated fabric) or even the sum of them. Inspired by the so-called "1 + 1 > 2" phenomenon, here we demonstrated that there was an EMI SE enhancement effect in this conductive polymer/metal system that may be associated with interphase chemical and/or physical interactions. Further analysis revealed that this EMI SE enhancement effect was evident under circumstances of relatively low metal content and became weak with the increase of metal content. The mechanisms involved were interpreted through a series of fundamental measurements, including Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and vector network analysis (VNA). The linkage between PANI and Co-Ni coatings was in the form of Co-N/Ni-N, which mimics the atomic configuration occurring in cobalt porphyrins. The Co-N/Ni-N configuration strengthened the interphase adhesion and thus resulted in shielding fabrics with high durability for practical applications.

Recent progress on nanostructured conducting polymers and composites: synthesis, application and future aspects

“…This stable composite film with a thickness of 10-15 µm displayed good shielding effectiveness of 30-35 dB with mechanical strength of 179 MPa. Zhao et al [421] synthesized a layer-structured shielding composite prepared by the successive coating of PANI and magnetic alloy cobalt-nickel which showed relatively high SE of 34-46 dB. Similar work was also achieved on layered linen fabric/PPy/nickel (LF/PPy/Ni) composites.…”

Chloride Ion Battery Review: Theoretical Calculations, State of the Art, Safety, Toxicity, and an Outlook towards Future Developments

“…Zhao et al [61] and Gschwind et al [38] both proposed the use of organic conductive polymers as the cathode. In one paper, polyaniline (PANI) was used in combination with a chlorideconducting polymer electrolyte.…”

“…They were also skeptical as to the "reduction" would work independently or whether chloride or some other species might be involved. [62][63][64][65] A completely different cathode material was proposed by Zhao et al, [61] who coated a carbon nanotube substrate with chloride-ion-doped polypyrrole (PPy) by means of a chemical oxidative polymerization procedure to yield a chloride-iondoped PPy cathode. A maximum capacity of 118 mA h g -1 was achieved.…”

“…Charge/discharge mechanism proposed by the authors of ref. [61] In that paper, the coordination of Clto an N + species in the pyrrole was proposed. Further investigation seemed to show that the PP 14 + cation in the electrolyte and TFSI can also intercalate.…”

Smart Textile Fabrics for Screening Millimeter Wavelength Radiations: Challenges and Future Perspectives

“…Recently, Zhao et al reported the fabrication of layered structure with lyocell fabrics, PANI and cobalt–nickel (Co–Ni) by electroless plating approach. The PANI/Co–Ni composites coated lyocell fabric exhibited high EMI SE of 46.22 dB in the X band region when compared to their single counterparts (PANI‐coated fabric and Co–Ni‐coated fabric) . The three phase heterostuctures of F‐NiFe2O4/PANI coated on Polyimide fabrics by layer by layer structure coating for EMI shielding applications was designed by wang et al .…”