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Abstract: The microwave absorption properties of the presented ternary composites are not satisfactory and the microwave absorption properties of the ternary composites composed of graphene, polypyrrole and Fe3O4 have never been reported. Herein, in order to expand the scope of microwave absorbers, the graphene/polypyrrole/Fe3O4 (GN/PPy/Fe3O4) composites were synthesized by a co-precipitation method. The microwave absorbability reveals that GN/PPy/Fe3O4 exhibits excellent microwave absorption properties and broad absorption bandwidths compared with GN, GN/PPy and GN/Fe3O4. The maximum reflection loss of GN/PPy/Fe3O4 is up to −56.9dB at 6.6GHz with a thickness of 5.3mm and the absorption bandwidths exceeding −10dB are more than 15.1GHz with a thickness in the range of 3–7mm. Furthermore, our strategy confirms that GN/PPy/Fe3O4 can be used as an attractive candidate for the new type of microwave absorbers. [Copyright &y& Elsevier]

Abstract: The ternary composites of reduced graphene oxide–polypyrrole–NiFe2O4 (RGO–PPy–NiFe2O4) were synthesized via a two-step method and the electromagnetic absorption properties were investigated. The average diameter of NiFe2O4 particles on RGO–PPy ranged from 10 to 20nm. The results revealed that the electromagnetic absorption properties and the absorption bandwidth of RGO–PPy–NiFe2O4 are much better than RGO–PPy. The maximum reflection loss of RGO–PPy–NiFe2O4 is −44.7dB at 14.9GHz and the absorption bandwidth with the reflection loss below −10dB is 4.7GHz with a thickness of 1.75mm. Furthermore, our strategy provides a feasible method to obtain the ternary composites with excellent electromagnetic absorption properties and wide absorption bandwidth for future investigators. [Copyright &y& Elsevier]

Abstract: Reduced graphene oxide (RGO)/CoFe2O4 composite was synthesized by a one-pot hydrothermal route, which avoided the usage of chemical reducing agent. The reduction of graphene oxide (GO) and the crystallization of CoFe2O4 crystals happened in a one step process by the hydrothermal method. The RGO/CoFe2O4 composite shows remarkably improved electromagnetic performance in comparison with CoFe2O4 NPs and reported pure RGO. Not only a larger reflection loss (−47.9dB at 12.4GHz), but also a wider absorption band (less than −10dB from 12.4 to 17.4GHz) has been achieved in the frequency range of 2–18GHz. It is believed that such composites could be used as a candidate microwave absorber. [Copyright &y& Elsevier]

Abstract: Novel composites composed of NiFe2O4 clusters and reduced graphene oxide were synthesized by using polyethylene oxide as a structure directing reagent and the microwave absorption properties of NiFe2O4 clusters-reduced graphene oxide (c-NiFe2O4/RGO) were investigated. The results indicate that NiFe2O4 clusters with diameters in the range of 40–70nm are composed of NiFe2O4 nanoparticles with diameters ranging from 3 to 5nm. The microwave adsorption properties show that the maximum reflection loss of c-NiFe2O4/RGO is up to −47.3dB at 11.9GHz and the absorption bandwidth with the reflection loss below −10dB is 4.7GHz with a thickness of 2.5mm. The excellent microwave absorption properties of c-NiFe2O4/RGO can be used as an attractive candidate for the new type of microwave absorptive materials. [Copyright &y& Elsevier]

Abstract: A novel kind of reduced graphene oxide (RGO)/Fe3O4/Ag composite was firstly synthesized by a rational route. The RGO/Fe3O4/Ag composite shows the maximum absorption of −58.1dB at 9.0GHz with the thickness of 2.6mm, and the absorption bandwidth with the reflection loss below −10dB is up to 13.4GHz (from 4.6 to 18.0GHz) with a thickness in the range of 1.5–4.0mm, suggesting that the microwave absorption properties and the absorption bandwidth are obviously enhanced by adding Ag NPs. It is believed that such composite could be used as a kind of candidate microwave absorber. [Copyright &y& Elsevier]

Abstract: The new ternary composite composed of RGO, Cu2O and Cu quantum dot was successfully synthesized at room temperature by using NaBH4 as reducing agent under mild wet-chemical conditions. The morphology, structure and microwave electromagnetic properties of the composite were characterized by XRD, XPS, TEM and vector network analyzer. The composite shows a large R L (−51.8dB at 14.6GHz) and a wide absorption band (less than −10dB from 12.1 to 16.2GHz) with the thickness of only 1.3mm. The enhanced microwave absorbing properties were also explained, and the loss mechanism is dielectric loss. The ternary composite can act as efficient and lightweight microwave absorbing material. [Copyright &y& Elsevier]

Abstract: Reduced graphene oxide–Co3O4 composites (RGO–Co3O4) were synthesized by a simple hydrothermal method and the electromagnetic and microwave absorbing properties of RGO–Co3O4 were investigated for the first time. The diameter of Co3O4 nanoparticles is in the range of 5–15nm. Electromagnetic parameters showed that the electromagnetic attenuation mechanism of RGO–Co3O4 is mainly dependent on dielectric loss. The resulting microwave adsorption properties showed that the maximum reflection loss of RGO–Co3O4 is up to −43.7dB at 13.8GHz and the absorption bandwidth with the reflection loss below −10dB is 4.6GHz with a thickness of 3.3mm. The excellent microwave absorption properties of RGO–Co3O4 can be used as an attractive candidate for the new type of microwave absorptive materials. [Copyright &y& Elsevier]

Abstract: The reduced graphene oxide (RGO) coated with Fe3O4 composite was synthesized through a facile one-pot simplified co-precipitation route, which avoided the usage of inert gas and any additional chemical agents (such as surfactants). Given these advantages, the strategy described in this study can be developed as a simple and large-scale yield route to RGO/Fe3O4 composite. The RGO/Fe3O4 composite shows the maximum absorption of −44.6dB at 6.6GHz with the thickness of 3.9mm, and the loss mechanism is mostly dielectric loss. It is believed that such composite will find its wide applications in microwave absorbing area. [Copyright &y& Elsevier]

Abstract: Tin-based oxides Li2SnO3 precursor and carbon-doped Li2SnO3 (Li2SnO3/C) nanocomposite with good cycle performance for lithium-ion batteries have been synthesized by sol–gel preparation and carbothermic reduction process. Results show that Li2SnO3/C is composed of regular rod nanoparticles (20–30nm) with clear lattice fringes, which exhibit better electrochemical properties than Li2SnO3. At a current density of 60mAg−1 in the voltage about 0.05–2.0V, the first discharge–charge capacities of the composite Li2SnO3/C are 1671.1mAhg−1 and 1558.6mAhg−1 while they are 1909.4mAhg−1 and 1745.8mAhg−1 to Li2SnO3. The retain capacity (576.9mAhg−1) of Li2SnO3/C is higher than that of Li2SnO3 after 50 cycles. [Copyright &y& Elsevier]

Abstract: Large-scale GdBO3:Eu3+ nanofibres with uniform diameter were controllably synthesized by a glycine-assisted hydrothermal method at 170°C using Gd(NO3)3, Eu(NO3)3 and Na2B4O7·10H2O as the precursors. X-ray diffraction (XRD) results show that the luminescent nanofibres are pure hexagonal structure and no other impurity phase appeared. Transmission electron microscopy (TEM) studies indicate that GdBO3:Eu3+ has a nanofibre structure. Photoluminescence (PL) spectra results demonstrate that the GdBO3:Eu3+ nanofibres have three strong 5D0 → 7F1 (595nm) and 5D0 → 7F2 (613 and 627nm) transition peaks corresponding to orange-red and red colors, respectively. [ABSTRACT FROM AUTHOR]