Currently, the development of low-reflection electromagnetic interference (EMI) shielding composite materials for mitigating secondary electromagnetic wave pollution has become a major research focus. However, achieving thinness, high toughness, low reflectivity, and multifunctionality in flexible EMI shielding films remains a challenge. To address this issue, this study introduces a "magnetic-electric" Janus structure EMI shielding composite film composed of MXene nanosheets, carbonized ZIF67 (CZIF67) nanoparticles and aramid nanofibers (ANF), balancing thinness, high toughness, low reflectivity and multifunctionality. As a result, the MXene/ANF-CZIF67/ANF-4 (MACA-4) sample exhibits high tensile strength (110.0 ± 7.0 MPa), large strain tolerance (21%), and superior toughness (14.9 ± 0.9 MJ·m-³), reflecting the stress dispersion effect of the 3D network structure of ANF and the strengthening effect of hydrogen bonding. The sample exhibits excellent flexibility, resistance to rubbing and folding. Even with a thickness of only 80 μm, the MACA-4 film exhibits a reflection performance (SER) as low as 4.3 to 4.5 dB in the 8.2 to 9.6 GHz band and the SET in the X-band reaches 44.8 dB. In addition, the superior conductivity of the MXene/ANF layer and the localized surface plasmon resonance effect give the MACA composite films excellent electrothermal conversion capabilities. Surprisingly, the sample also exhibited excellent infrared stealth and fire alarm properties. This work offers valuable guidance on the fabrication of ultra-thin flexible EMI shielding composites and provides an important scientific basis for the design and application of efficient EMI shielding materials.
Flower-like cobalt–molybdenum mixed-oxide microspheres (CoMo-FMs) with hierarchical architecture were successfully synthesized via a hydrothermal process and subsequent calcination step. The characterization results show that CoMo-FMs were assembled from ultrathin mesoporous nanosheets with thicknesses of around 4.0 nm, providing the composite with a large pore volume and a massive surface area. The synthesized CoMo-FMs were employed as catalysts for the aerobic oxidative desulfurization (AODS) of fuel, and the reaction results show that the optimal catalyst (CoMo-FM-2) demonstrated an outstanding catalytic performance. Over CoMo-FM-2, various thiophenic sulfides could be effective removed at 80–110 °C under an atmospheric pressure, and a complete conversion of sulfides could be achieved in at least six consecutive cycles without a detectable change in chemical compositions. Further, the catalytic mechanism was explored by conducting systemic radical trapping and transformation experiments, and the excellent catalytic performance for CoMo-FMs should be mainly due to the synergistic effect of Mo and Co elements.
14 June 2019 in Zeitschrift für Kristallographie - New Crystal Structures
C7H4CuF6NO4, triclinic, P (1) over bar (no. 2), a = 8.5122(5) angstrom, b = 8.5458(6) angstrom, c= 8.8674(6) angstrom, alpha = 75.042(3)degrees, beta = 68.601(2)degrees, gamma = 89.809(3)degrees, V = 577.26(7) angstrom(3), Z = 2, R-gt(F)= 0.0247, WRref(F-2) = 0.0625, T = 152.41 K.
C 19 H 14 Br 3 CdF 6 N 3 O 5 , triclinic, P 1‾$‾{1}$ (no. 2), a = 9.2591(4) Å, b = 9.6573(5) Å, c = 16.9256(9) Å, α = 102.707(2) Å, β = 96.854(2) Å, γ = 112.550(2) Å, V = 1328.20(12) Å 3 , Z = 2, R gt ( F 2 ) = 0.0291, wR ref ( F 2 ) = 0.0625, T = 150.15 K.