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The damping properties of Al matrix composite foams reinforced by in-situ grown carbon nanotubes (CNTs) have been investigated. The results show that the damping capacity of the CNT/Al composite foams is visibly enhanced with the CNT addition. The loss factors of the composite foams are found not only increase with the increment of CNT content but also increase with the porosity raising. For the 3.0 wt%-CNT/Al composite foams, the loss factor keeps the level of ∼0.26 at 25–200 °C and further increases to 0.36 when the temperature is elevated to 390 °C, which is ∼2.71 and 1.77 times higher than that of the pure Al foam, respectively. The damping improvement of CNT/Al composite foams is mainly due to the high inherent damping of CNTs and the formation of large numbers of well-bonded CNT-Al interfaces. [ABSTRACT FROM AUTHOR]

Abstract: Novel binary and triple carbon nanotubes (CNTs) with one common catalytic particle encapsulated have been synthesized using Ni/Cu/Al2O3 catalyst, which was produced by a sol–gel method. But when using Ni/Al2O3 as catalyst, a mass of common CNTs, that is, one CNT with one catalytic particle encapsulated, was obtained. The results showed that copper-element doping to the Ni/Al2O3 catalyst played a key role in the synthesis of CNTs, signifying a novel approach to modify the Ni/Al2O3 catalyst. Based on the transmission electron microscopy observations, a simple growth mechanism was developed to describe the growth of the binary or triple CNTs, which could be well explained by a diffusion segregation process. [Copyright &y& Elsevier]

Abstract: The reduced graphene oxide (r-GO) coated with Fe3O4 composite was synthesized through a facile method involving decomposition of Fe(OH)3 in argon atmosphere and reduction in hydrogen and argon mixture atmosphere. The Fe3O4 particles evenly distributed on r-GO, with the diameters from 10nm to 40nm, are monocrystalline. The composite demonstrates a reflection loss below −10dB in 14.3–18GHz range, and the maximum absorption of −22.2dB at 17.3GHz. The microwave absorption of r-GO/Fe3O4 nanocomposites is attributed to relaxation and polarization of the residual groups and defect of graphene and polarization attributed to the presence of Fe2+ ions in Fe3O4. [Copyright &y& Elsevier]

Abstract: TiO2 nanoparticles are widely used in dye-sensitized solar cells (DSSCs). The combination of one-dimensional materials such as carbon nanotubes (CNTs) with TiO2 nanocrystals by mechanical mixing has been expected to improve the electron transport of anode. However, these methods cannot ensure the connection between one-dimensional materials and collector, which is the key for exerting the fast electron transport property. In this study, a novel synthesis method named gel chapping for CNTs/TiO2 nanocomposites preparation is presented, in which porous nanocrystalline TiO2 film with through-hole cracks is fabricated. By using the porous films with cracks as templates, CNTs are deposited in pores and well connected with the template and current collector which favors the transportation of electrons. The current–voltage curve test reveals that the conversion efficiency of CNTs/TiO2 nanocrystalline composite structures is 2.6 times superior to TiO2 nanocrystalline film. [Copyright &y& Elsevier]