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The lithium storage properties of hollow ZnO/Cu2MgO3 nanocages with porous outer shell as an efficient anode material for next generation lithium-ion battery (LIB) are demonstrated for the first time. The ZnO/Cu2MgO3 nanocages as anode material are synthesized by one-step cost-effective ultrasonic spray pyrolysis method. The porous outer shell with hollow interior not only offer ease of electrolyte diffusion and fast Li-ion transport, but also buffer the huge volume change during repeated lithiation/de-lithiation process. As a result, this novel anode demonstrates a high discharge capacity (441 mA h g-1 at the current density of 500 mA g−1 even after 400 cycles), excellent cycle stability, and outstanding rate capability.

This work inspects the effect of different sintering atmospheres on the microstructure behavior and grains morphology of pressureless sintered SiC/AlN ceramic composites. Different SiC/AlN composites with different AlN content (0–40 wt%) were prepared by pressureless sintering at 2080 °C/2 h with addition of 2.5 wt% yttria and alumina as sintering aids. Microstructure investigation of the different carbide/nitride composites were studied under two different sintering atmospheres of argon (Ar)/vacuum and nitrogen (N2)/vaccum. Densification parameters of the different composites were measured and evaluated. Results showed that, SiC/AlN composites gave homogenous microstructure with expected high temperature properties. However they manifested different demeanors under the different atmospheres. Sintering of different composites in Ar/vacuum atmosphere was found the most suitable with high density and harmonic structure. Cold crushing strength (CCS) of the composites of the chosen atmosphere was studied and analyzed. Different SiC/AlN composites gave superior strength values resulted from the good bonding and diffusion between SiC and AlN besides their solid solution reaction. Results suggest using the investigated composites in aggressive high mechanical and high temperature applications.

A new nanocomposite has been prepared embedding CuO nanoparticles as an additive into grafted β-nickel hydroxide electrode and their electrochemical performance in KOH electrolyte have been investigated. β-nickel hydroxide (β-Ni(OH)2) has been prepared by a simple precipitation method. Ni(OH)2/NiOOH, the main active materials in the pasted nickel electrode have been prepared using nickel mesh in the form of current collector. A study on the electrochemical performances of the pure β-Ni(OH)2 and CuO added β-Ni(OH)2 electrodes in 6.0 M KOH electrolyte has revealed that CuO embedded β-Ni(OH)2 displays much higher specific capacitance and better cyclability than pure β-Ni(OH)2. In fact, the addition of CuO improves the reversibility of the electrode by reducing the anodic (Epa) and cathodic (Epc) peak potential difference and also increases the separation of the oxygen evolution (EOE) and anodic (Epa) peak potential. Further, CuO nanoparticles grafted β-Ni(OH)2 electrode displays elevated proton diffusion co-efficient (D) and inferior charge transfer resistance. Specifically, CuO embedded β-Ni(OH)2 exhibits 855 F g−1 at 5 Ag-1 and good cycling stability as it maintains more than 90% of its original capacitance even after 3000 cycles. The enhancement may be attributed to the nanosize of CuO and chemical interaction between CuO and β-Ni(OH)2. These results are expected to offer new insight to future researchers who wish to work on the development of novel electrode materials for energy storage applications.

This study is focused on finding a versatile approach for obtaining low cost, lightweight composites with high thermal conductivity and good mechanical properties at the same time. The most promising application for such material is to replace fabric reinforced laminates in circuit board production. We used high density polyethylene (HDPE) as a polymer matrix and two types of hexagonal boron nitride (hBN) powders with average particle size 2–5 μm and 120–140 nm as a functional filler. To improve both filler-matrix adhesion and mechanical properties of the composites we used one of two techniques: treating the filler with silane coupling agent before composite processing or using titanate coupling agent in the process of roller-mixing. The study showed, that while the best thermal conductivity of 2 W/m K was achieved on the sample prepared without any coupling agent the sample was too brittle for further processing. On the other hand the sample with KR TTS additive and HDPE to hBN ratio 1:1 showed quite high ultimate strength of 24.8 MPa coupled with high Young's modulus, good elongation at break and thermal conductivity of 0.9 W/m K. Usage of hBN nanopowder as a filler resulted in good mechanical properties and high elongation at break values with thermal conductivity values significantly lower than for micro-sized fillers (0.43 W/m K).

Novel hollow-structured Cu0.4Zn0.6Fe2O4 porous negative electrode material is synthesized using a one-step spray pyrolysis method, which exhibits excellent rate capability, high cycling stability, and fast charge-discharge performance in Li-ion batteries. Evaluation of lithium storage properties reveals that the hollow Cu0.4Zn0.6Fe2O4 nanospheres exhibit high specific capacity of 1122 mAh g−1 at a current density of 100 mA g−1, excellent rate capabilities up to 1500 mA g−1 and long term cycling stabilities at a high rate of 1000 mA g−1. Interestingly, the hollow cavity and porous textures of the Cu0.4Zn0.6Fe2O4 anode are well retained even after 1000 cycles at 1000 mA g−1. The synergistic effect among the different cations, as well as the nano-dimension coupled with a hollow interior and surface porosity of the electrode materials, not only facilitate Li-ion and electron transportation kinetics but also accommodate large volume expansion.

In this article, for the first time, we are reporting on the electrochemical lithium storage properties of hollow Mg 0.25 Cu 0.25 Zn 0.5 Fe 2 O 4 /NiFe 2 O 4 nanocomposites. The nanocomposites exhibit excellent cycling performance with a capacity of 661 and 460 mA h g −1 after 500 cycles at a very high rate of 300 and 1000 mA g −1 , respectively. Such superior performance over other Fe based mixed metal oxides is produced by the combination of the composite and the hollow structures. In virtue of the excellent electrochemical performance, hollow Mg 0.25 Cu 0.25 Zn 0.5 Fe 2 O 4 /NiFe 2 O 4 nanocomposites have huge potential as anode materials for the next-generation lithium ion batteries.

In the relentless pursuit of finding new electrode materials for lithium ion batteries (LIBs), mixed metal oxides (MMOs, containing different metal cations), have confirmed improved electrochemical activities in comparison with simple metal oxides (SMOs, containing single metal cations). On the other hand, electrodes with nano-dimension and hollow microstructure have been confirmed as advantageous candidate in LIBs. The integration of the two features into one structure can provide another chance to improve the lithium storage capabilities. In this work, for the first time we report the lithium storage property of porous Cu0.10Mg0.40Zn0.50Fe2O4/Ca2Ni5 nanocomposite as LIB anode. The nanocomposites anode delivers approximately 350 mAh g−1 after 500 cycles at 300 mA g−1. Even at a high rate of 1000 mA g−1, it also showed an excellent performance up to 1000 cycles and 90% Coulombic efficiency with no sign of capacity fading. This outstanding Li storage performance makes Cu0.10Mg0.40Zn0.50Fe2O4/Ca2Ni5 nanocomposites a promising candidate as LIB anode.

Products made of polypropylene (PP) are subject to photodegradation under UV-radiation leading to a change in the physical characteristics of the polymer. The addition of UV-filters, like ZnO nanoparticles, contribute to absorb UV-radiation and protect the polymer matrix. In this study ZnO nanopowder with a particle size of 50 nm was modified by 3-aminopropyltriethoxysilane (APTES) and introduced into the PP matrix. The optimal concentration of nanoparticles was determined. PP-films with a thickness of 100 and 200 μm were obtained. Structural and mechanical characteristics before and after irradiation by UV-radiation were studied by means of FTIR-spectroscopy, XRD, DSC, UV-VIS spectrophotometry and tensile tests. It was observed that UV irradiation of PP leads to the break of molecular chains, therefore releasing more molecular segments released. These segments can move and form a new crystal structure in the initial amorphous phase. The oxidation index of PP increased due to the formation of ketones. ZnO nanoparticles modified by APTES acted as nucleation sites and γ-phase was formed in the polymer. Also, the addition of ZnO-APTES nanoparticles in the polymer promoted absorption of UV-radiation in the wavelength range of 200–400 nm, thus protecting the polymer from degradation.

Transition metal trichalcogenides (TMTCs), such as TiS3 and ZrS3, attract growing interest because of their peculiar quasi-one-dimensional (quasi-1D) structure and promising electronic properties. In this study, we investigated Zr1-xTixS3 solid solutions and demonstrated that they could be prepared through the direct reaction between Zr–Ti alloys and sulfur vapor at 800 °C. We varied the Zr/Ti atomic ratio in the alloys from 80/20 to 20/80 and found that in all cases the resulting solid solution crystals had a composition close to Zr0.8Ti0.2S3. The excessive titanium, if present, formed the secondary TiS2 phase, which was detected by the powder X-ray diffraction (XRD) analysis and observed in scanning electron microscopy (SEM) images in the form of hexagonal crystals. The Zr1-xTixS3 solid solutions formed distinct needle-like crystals, whose shape was consistent with the quasi-1D structure of TMTCs. We demonstrated that these crystals could be mechanically exfoliated into thin nanoribbons by an adhesive tape approach and used for device fabrication and electrical measurements. The transport measurements of Zr0.82Ti0.18S2.86 devices revealed their n-type conductivity and electron mobility of about 2 cm2 V−1 s−1, as well as photoresponse to visible light.

Boron and aluminium nitride, as well as carbon materials, were used as fillers for polypropylene to increase its thermal conductivity. Better thermal conductivity was observed for samples filled with nanosized BN. All composites show thermal stability up to 250 °C. Filling of polypropylene was shown to affect crystallinity degree, adding of BN and carbon nanotubes results in the increase in crystallinity of polypropylene. It was observed that BN forms chemical bonds with polymer matrix, whereas no evidence of such bonds was found in case of polypropylene filled with AlN particles.

Multilayer coatings were deposited on carbide cutting inserts with an Arc-PVD method using a cathodic vacuum arc evaporation apparatus equipped with three disposed flat arc cathodes (Ti–Al, Zr–Nb and Cr). The samples were obtained under different deposition conditions: an arc current at the Zr–Nb cathode, a rotation speed of the samples coated relative to evaporated cathodes and a substrate bias. The mechanism of formation of the structure and phases in the material of the Ti–Al–N/Zr–Nb–N/Cr–N coating are established depending on the parameters of cathodic vacuum arc ion-plasma evaporation. It is established that the introduction of an additional Zr–N-based barrier layer to a multilayer nanostructure between the mutually soluble Ti–Al–N and Cr–N layers results in the enhancement of its thermal stability. The coatings are characterized by high hardness, Young’s modulus and the work of plastic deformation.

Polypropylene-based composites filled with multiwall carbon nanotubes were prepared using twin-screw extrusion technique. Two types of nanotubes with different diameter, morphology and defectiveness were used as fillers. Influence of MWNT surface composition on properties of the composite was investigated for oxidized nanotubes. Thermal conductivity (TC) of MWNT/PP composites with different MWNT concentration was investigated, showing strong dependence of TC value on the MWNT type and structure, and MWNT content in composite. TC value of 0.55-0.6 W/m × K was achieved for MWNT/PP samples filled with 16 wt.% of low-defective MWNTs with mean diameter 22 nm. © 2012 Elsevier B.V. All rights reserved.