Laminated MXene Foam/Cellulose@LDH Composite Membrane with Efficient EMI Shielding Property for Asymmetric Personal Thermal Management

Exploring the Potential of Sustainable Biopolymers as a Shield against Electromagnetic Radiations

The increasing demand for biodegradable and environmentally friendly materials is shifting the focus from traditional polymer composites to biocomposites in various applications, especially in electromagnetic shielding. Effective utilization of biopolymers demands improved properties and can be achieved to a certain extent by functionalization. Biopolymers such as cellulose, polylactic acid, and starch are some of the potential candidates for mitigating electromagnetic pollution in next-generation electronic devices because of their high aspect ratio, flexibility, light weight, high mechanical strength, thermal stability, and tunable microwave absorption to the electromagnetic interference (EMI) shielding composites. This Review provides an overview of the current advancements in EMI shielding materials and outlines recent research on EMI shielding composites that utilize various biodegradable polymer structures.

Fabrication of highly conductive, flexible, and hydrophobic Kevlar®@Ni-P-B@Cu@CS fabric with excellent self-cleaning performance for electromagnetic interference shielding

In this work, a simple and cost-effective method was proposed and developed to prepare a novel multilayer-structured Kevlar®@nickel-phosphorus-boron@copper@copper stearate (Kevlar®@Ni-P-B@Cu@CS) composite fabric with high conductivity, high flexibility, high hydrophobicity, and high durability to effectively shield electromagnetic interference (EMI). In this method, an amorphous Ni-P-B alloy nanolayer was initially deposited onto a Kevlar® fabric via electroless plating. Afterward, a crystalline Cu nanolayer was deposited as the second layer via electroplating. Finally, a monolayer of copper stearate was innovatively self-assembled as the outermost protective layer. The Cu deposition was effectively adjusted and designed by controlling the plating current and plating time. The electrical resistance and contact angle of the optimized Kevlar®@Ni-P-B@Cu@CS composite fabric were as low as 3.2 mΩ sq-1 and as high as 115.39°, respectively, indicating that the fabric could withstand bending, tape-off, corrosion, and accelerated environmental tests. The average EMI-shielding efficiency of the durable composite fabric was 93.9 dB in the frequency range of 8.2-12.4 GHz, which was mainly attributed to the absorption loss. Thus, the proposed material configuration has promise for applications in aviation, aerospace, telecommunication, wearable devices, and military industries.

Preparation of NiS/Ti3C2Tx co-doped with N and P at the covalent interface and its electromagnetic wave absorption properties

The harm of electromagnetic waves on human daily life has gradually received attention, and electromagnetic waves absorption materials have been used to address this issue. MXene, as a new type of 2D material, is a very promising electromagnetic wave absorption material. In this study, NiS nanoparticles were grown on the surface of S terminated Ti3C2Tx, and -S group acted as sulfur sources to construct Ti-S-Ni covalent interface directly in NiS/Ti3C2Tx composites. To further regulate the interface structure and electromagnetic properties, -P and -NH2 groups were also introduced onto the surface of MXene to achieve the N, P co-doping NiS/Ti3C2Tx composites with covalent interface. By investigating the electromagnetic wave absorption performance of the composites, it was found that N and P doping could effectively enhance the electron transfer rate at the interface and optimize the conduction loss, resulting in a significant improvement in performance. The minimum reflection loss was -50.6 dB at a frequency of 15.6 GHz, and the matching thickness was only 1.14 mm with an effective absorption bandwidth of 3.6 GHz. These results provide an important references and guidance for further research and development of high-performance electromagnetic wave absorption materials.