Two-dimensional (2D) layered materials assume a central role in efforts to address the challenges associated with electromagnetic interference (EMI) due to undesirable effects of continuous exposure to electromagnetic fields. Recent progress on EMI shielding effectiveness (EMI SE) of 2D layered materials is highlighted, such as black phosphorus, hexagonal boron nitride, layered double hydroxides, and transition metal dichalcogenides, with a focus on the significant volume of work done with MXenes. The 2D structures yield large surface area and low density, and their unique electrical properties confer them a high potential for developing superior EMI shielding materials. Commercial products of EMI shielding materials are analyzed, and we discuss how these 2D materials could reach the market.

layered materials are currently one of the most explored materials for developing efficient and stable electrocatalysts in energy conversion applications. Some of the 2D metal phosphorous trichalcogenides (M 2 P 2 X 6 or MPX 3 in its simplified form) have been reported to be useful catalysts for water splitting, although results have been less promising for the sluggish oxygen evolution reaction (OER) due to insufficient activity or compromised stability. Herein, we report the OER catalysis of a series of M 2 P 2 X 6 (M 2+ = Mn, Fe, Co, Zn, Cd; X = S, Se). From the series of MPX 3 , CoPS 3 yields the best results with an overpotential within the range of values usually obtained for IrO 2 or RuO 2 catalysts. The liquid-phase exfoliation of CoPS 3 even improves the OER activity due to abundant active edges of the downsized sheets, accompanied by the presence of surface oxides. The influence of the OER medium and underlying substrate electrode is studied, with the exfoliated CoPS 3 reaching the lowest overpotential at 234 mV at a current density of 10 mA/cm 2 , also able to sustain high current densities, with an overpotential of 388 mV at a current density of 100 mA/cm 2 , and excellent stability after multiple cycles or long-term operation. Quantum chemical models reveal that these observations are likely tied to moieties on CoPS 3 edges, which are responsible for low overpotentials through a two-site mechanism. The OER performance of exfoliated CoPS 3 reported herein yields competitive values compared to those reported for other Co-based and MPX 3 in the literature, thus holding substantial promise for use as an efficient material for the anodic water-splitting reaction.

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In this work, a method for preparation of polyamide-6 (PA6) based laminates reinforced by glass fiber-(GFL) or polyamide-66 (PA66) textile structures (PL) via reactive injection molding is disclosed. It is based on in-mold anionic polymerization of e-caprolactam carried out at 165 C in the presence of the respective reinforcements performed in newly developed prototype equipment whose design concept and operation are described. Both composite types were produced for reaction times of 20 min, with conversion degrees of 97-99%. Initial mechanical tests in tension of GFL samples displayed almost twofold increase of the Young's modulus and stress at break values when compared with the neat anionic PA6. The improvement was proportional to the volume fraction V f of glass fiber fabric that was varied in the 0.16-0.25 range. A 300% growth of the impact strength was registered in PL composites with V f of PA66 textile of 0.1. Removing the surface finish of the latter was found to be a factor for improving the adhesion at the matrix-fiber interface. The mechanical behavior of GFL and PL composites was discussed in conjunction with the morphology of the samples studied by optical and electron microscopy and the matrix crystalline structure as revealed by synchrotron X-ray diffraction.

The pursuit of materials to avoid problems associated with electromagnetic pollution has become a relevant research topic. Here, we report the exceptional electromagnetic interference (EMI) shielding performance of freestanding reduced graphene oxide (rGO) foil produced by thermal reduction of graphene oxide (GO). The rGO foil with a thickness of 93.1 ± 12.4 μm reaches an efficient EMI shielding effectiveness (SE) value of 61.6 dB at 12.4 GHz. The excellent performance of the rGO foil is attributed to the thermal reduction of the GO foil, which restores the electrically conductive network, resulting in the electrical conductivity of 1.17 × 104 S m–1. To obtain a more complete profile of the EMI shielding performance of the rGO foil, measurements are performed in G- and C-bands, thus becoming the first study on the EMI shielding performance of an rGO film on a broad frequency range beyond the so-called X-band. The material sustains an EMI shielding efficiency higher than 99.999% over the frequency bands investigated, greatly desired in a wide range of commercial applications in this field.