In this study, the electromagnetic wave absorption properties of woven glass fiber reinforced epoxy composites with Sb2O3 and SnO2 nanoparticles doped mica pigments were investigated. Herein, we synthesized SnO2/mica, Sb2O3/mica, and Sb2O3:SnO2/mica pigments using the sol–gel method. Subsequently, mica pigments filled glass fiber/epoxy composite panels were fabricated with a vacuum assisted resin mold. The phase, crystal, and morphological examinations of particles confirm the deposition of SnO2 and Sb2O3 nanoparticles on the mica surfaces. The electromagnetic wave absorption properties of samples were measured using the S parameters and obtained dielectric data. Sb2O3:SnO2/mica particles display higher complex permittivity and dielectric loss values due to the strong interfacial polarization between conductive nano metal‐oxide shells and mica surfaces. According to the calculated reflection loss values, Sb2O3:SnO2/mica particles exhibit superior electromagnetic wave absorption performance with a minimum reflection loss of −25.62 dB for 2.4 mm thicknesses with effective bandwidth between 9.3 and 12.4 GHz. The S parameters of the prepared structural composites with the size of 30 cm × 30 cm × 3 mm was determined by the free‐space technique using the transmission line technique. According to the S12 parameters, filled glass fiber/epoxy composite containing 25 wt% Sb2O3:SnO2/mica show a minimum reflection loss of −20.426 dB at 8.2 GHz with effective bandwidth between 8.2 and 9.67 GHz. These results indicate that Sb2O3:SnO2/mica‐filled fiber/epoxy composite is an excellent candidate for the practical application of electromagnetic wave absorbers.

Summary MXene, which are known as two‐dimensional transition metal carbides have received heavy interest due to their rich elemental diversity and many fascinating physical and chemical properties. Here, Rh (0) nanoparticles deposited MXene catalysts were synthesized by an easy wet‐impregnation method for hydrogen production. Rh (0) nanoparticles were conveniently loaded on the surface of MXene (Rh/MXene) were used as an effective nanocatalyst for the hydrogen production from the hydrolysis of ammonia‐borane (AB). The morphological and structural characterizations of Rh/MXene catalysts show that Rh nanoparticles were successfully deposited on the surface of MXene substrates. Rh (0) nanoparticles with an average size of 2.55 nm were homogeneously dispersed and deposited on the MXene surface. The Rh/MXene displayed good catalytic performance in the hydrogen production via the hydrolysis of AB, and the turnover frequency value at 25°C was 288.4 min−1, which is comparable to most of the synthesized catalysts. The Rh/MXene catalyst displaying good activity in seven consecutive catalytic cycles can be considered a good nanocatalyst candidate for hydrogen production from the hydrolysis of AB.

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The CuO deposited barite pigments (CBP) were obtained by direct deposition method. Optic and dielectric properties of nanocomposites were investigated. Hence, the prepared pigments were structural scanning electron microscope (SEM). The optic properties of pigments were evaluated with ultraviolet–visible spectrophotometer (UV-Vis). The scanning electronic microscopy results show that barite was coated with CuO uniformly. The UV-Vis results show that CuO deposited barite pigments (CBP) have high ultraviolet shielding performance. Furthermore CuO deposited barite pigments (CBP) exhibited UV-Vis reflectance than those of pure-CuO. Furthermore, the conductivity of barite flakes increased with the coating of CuO nanoparticles. The dielectric properties of CuO deposited barite pigments were determined in the frequency range of 8.2–12.4 GHz via vector network analyzer and the electromagnetic absorption properties of nanocomposite was determined and calculated by using these dielectric values (permittivity). CuO deposited barite/epoxy nanocomposite (mass ratio is 3:10) with 2 mm thickness showed a minimum reflection loss of -9 dB at 12.25 GHz frequency. Furthermore, the conductivity of barite flakes increased with the coating of CuO nanoparticles.