Near-Instantaneously Self-Healing Coating toward Stable and Durable Electromagnetic Interference Shielding

Abstract

Durable electromagnetic interference (EMI) shielding is highly desired, as electromagnetic pollution is a great concern for electronics’ stable performance and human health. Although a superhydrophobic surface can extend the service lifespan of EMI shielding materials, degradation of its protection capability and insufficient self-healing are troublesome issues due to unavoidable physical/chemical damages under long-term application conditions. Here, we report, for the first time, an instantaneously self-healing approach via microwave heating to achieve durable shielding performance. First, a hydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane (POTS) layer was coated on a polypyrrole (PPy)-modified fabric (PPy@POTS), enabling protection against the invasion of water, salt solution, and corrosive acidic and basic solutions. Moreover, after being damaged, the POTS layer can, for the first time, be instantaneously self-healed via microwave heating for a very short time, i.e., 4 s, benefiting from the intense thermal energy generated by PPy under electromagnetic wave radiation. This self-healing ability is also repeatable even after intentionally severe plasma etching, which highlights the great potential to achieve robust and durable EMI shielding applications. Significantly, this approach can be extended to other EMI shielding materials where heat is a triggering stimulus for healing thin protection layers. We envision that this work could provide insights into fabricating EMI shielding materials with durable performance for portable and wearable devices, as well as for human health care."Image missing"

Functional Polyaniline/MXene/Cotton Fabrics with Acid/Alkali-Responsive and Tunable Electromagnetic Interference Shielding Performances

“…Because the electromagnetic interference (EMI) and radiation pollution derived from various modern communication and electronic devices severely endanger the reliability of precision equipment, information security, and even human health, , high-performance EMI shielding materials and composites are highly required. − Over the past decade, numerous attempts have been devoted to design and fabricate multifunctional EMI shielding fabrics for shielding electromagnetic wave interference and radiation. − To date, various electrically conductive nanomaterials are decorated onto the flexible fabric substrates for EMI shielding by spray coating, dip coating, drop casting, electroless plating, vacuum filtration, and combination of spray coating with vacuum-assisted filtration . The conductive materials used include metallic nanomaterials (Ag, Ni), , carbon nanomaterials (carbon nanotube, reduced graphene oxide), , intrinsic conducting polymers (polypyrrole (PPy), polyaniline (PANI)), , and liquid metals . The newly emerged two-dimensional (2D) transition-metal carbides (MXenes) with high intrinsic conductivity, favorable hydrophilicity, and large specific surface area would be promising constituent blocks for constructing highly efficient conductive networks, , and especially for preparing EMI shielding fabrics. , For example, Wang et al fabricated highly conductive and hydrophobic textiles by depositing in situ polymerized PPy-modified MXene sheets onto poly­(ethylene terephthalate) textiles followed by silicone coating.…”

“…6−10 To date, various electrically conductive nanomaterials are decorated onto the flexible fabric substrates for EMI shielding by spray coating, 11 dip coating, 12 drop casting, 13 electroless plating, 14 vacuum filtration, 15 and combination of spray coating with vacuum-assisted filtration. 16 The conductive materials used include metallic nanomaterials (Ag, Ni), 17,18 carbon nanomaterials (carbon nanotube, reduced graphene oxide), 19,20 intrinsic conducting polymers (polypyrrole (PPy), polyaniline (PANI)), 21,22 and liquid metals. 23 The newly emerged two-dimensional (2D) transition-metal carbides (MXenes) with high intrinsic conductivity, favorable hydrophilicity, and large specific surface area would be promising constituent blocks for constructing highly efficient conductive networks, 24,25 and especially for preparing EMI shielding fabrics.…”

Absorption-Dominant, Low-Reflection Multifunctional Electromagnetic Shielding Material Derived from Hydrolysate of Waste Leather Scraps

“…Figure c displays a comparison of EMI shielding performance with composite material thickness to emphasize the major benefits of the Co@CNF nanofiber film. Notably, the Co@CNF nanofiber film exhibits a higher EMI shielding performance per unit thickness compared to previously reported leading EMI shielding composites, such as CNNFFs, PPy@POTs, C@CoFe, CF@NiCo/PI, LSW/PVA/PANI, silicone rubber/Ag, and CNF/Ag . The Co@CNF nanofiber films are suitable for further development of a new generation of multifrequency, lightweight, and intelligent electromagnetic shielding materials.…”

“…35,36 EMI shielding materials are prone to oxidation and structural collapse under harsh conditions such as moisture, corrosion, etc. 37 Therefore, a protective layer of materials for EMI shielding materials, such as poly(vinylidene fluoride), 38 polyurethane, 39 poly(dimethylsiloxane), 40 silicon, 41 and perfluorooctyltriethoxysilane (POTS), 42 has been reported to extend the stability and durability of shielding performance. The role of the protective layer is to prevent the aqueous solution from invading the EMI shielding material, giving the film stable performance in harsh environments.…”

Identification of the Intrinsic Dielectric Properties of Metal Single Atoms for Electromagnetic Wave Absorption

“…The stability is also important for the practical application of 3D Mn–NC [ 50 ]. Firstly, the 3D Mn–NC sample was fabricated through a strong acid etching process, and thus it is characterized by good acid corrosion resistance.…”