Strontium ferrite nanoparticles were prepared by a coprecipitation method, and reduced graphene oxide/strontium ferrite/polyaniline (R-GO/SF/PANI) ternary nanocomposites were prepared by in situ polymerization method. The morphology, structure, and magnetic properties of the ternary nanocomposites were investigated by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), TEM, Raman, and VSM. The microwave-absorbing properties of the composites were measured by a vector network analyzer. The XRD patterns show the single phase of strontium hexaferrite without other intermediate phases. TEM photographs reveal that strontium ferrite nanoparticles are uniformly dispersed on the surfaces of R-GO sheets. The R-GO/SF/PANI nanocomposite exhibited the best absorption property with the optimum matching thickness of 1.5 mm in the frequency of 2–18 GHz. The value of the maximum RL was −45.00 dB at 16.08 GHz with the 5.48-GHz bandwidth. The excellent absorption properties of R-GO/SF/PANI nanocomposites indicated their great potential as microwave-absorbing materials.

Ba 0.9 La 0.1 Fe 11.9 Ni 0.1 O 19 nanoparticles were prepared by a co-precipitation method, and Ba 0.9 La 0.1 Fe 11.9 Ni 0.1 O 19 /reduced graphene oxide/polyaniline ternary nanocomposites (BF/RGO/PANI) were prepared by in situ polymerization. Microwave reflection loss, and the permittivity and permeability of BF/RGO/PANI nanocomposites were investigated in the frequency range 2-18 GHz. The prepared samples possessed excellent electromagnetic wave-absorbing performances, and the optimal impedance matching of BF/RGO/PANI nanocomposites was found. The minimum reflection loss reached À49.1 dB near the frequency of 14.08 GHz with a thickness of 1.9 mm and its absorption bandwidth with a reflection loss below À10 dB ranged from 12.4-16.72 GHz with a bandwidth of 4.32 GHz. Our study illustrates that the as-prepared BF/RGO/PANI nanocomposites are promising candidates for use in electromagnetic wave-absorbing materials.

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Two new coordination polymers, [Ni(H2O)(Hpdcd)(H2O)2]·DMF (1) and [Co(H2O)(Hpdcd)(H2O)2]·DMF (2) (H3pdcd = 1-(4-carboxyphenyl)-2,5-dimethyl, 1H-pyrrole-3,4-dicarboxylic acid), which were designed based on a tertiary amine ligand, were synthesized and characterized using multiple spectroscopy techniques, including single-crystal X-ray diffraction. These two 1D linear chains possess the properties of both a Lewis acid and organic base, which was confirmed by temperature programmed desorption of ammonia and on-line mass spectrometry (NH3-TPD-MS), and selective sorption for carbon dioxide. Due to their acid-base properties, the compounds exhibited high catalytic activity, in the absence of co-catalysts, for solvent-free synthesis of chloropropene carbonate from CO2 and epichlorohydrin under atmospheric CO2 pressure. The yields of chloropropene carbonate were 88% and 87% for 1 and 2, respectively, under the optimized conditions.