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The microstructure and characterization of Sn–Zn–Cu–Ni (SZCN) solder alloy reinforced with TiO2 and ZrO2 nanoparticles (NPs) synthesized by powder metallurgy were investigated. Sn, Zn, Cu and Ni metallic powders were mixed mechanical by 10:1 ball to powder ratio with 300 rpm speed for 2 h. Then 0.5 wt% from nano ZrO2 or TiO2 was mixed by the same parameters with the mixed metal powder. The morphologies and microstructures development during the fabrication process was investigated by X-ray diffractometer (XRD), optical microscope (OM), and scanning electron microscope (SEM) with energy dispersive X-ray spectrometry (EDX). The results reveal an improved distribution of TiO2 or ZrO2 NPs in the SZCN matrix solder, which resulted in an improvement in its density. The analyses of microstructural demonstrated that the addition of TiO2 or ZrO2 NPs to SZCN solder results in the grain refinement of the β-Sn phase, besides the formation of Ni3Sn IMC with small size and uniform distribution. The microhardness was enhanced as a result of the addition of TiO2 or ZrO2 NPs. The experimental results showed that the SZCN-ZrO2 composite solder had the greatest hardness and stress exponent values due to its effectiveness in suppressing the growth of β-Sn grains and the pile-up of dislocations. Both the electrical and thermal conductivities were improved by incorporating TiO2 NPs compared to other solders. [ABSTRACT FROM AUTHOR]

New metal oxide-metal chalcogenide system composed of TiO2@SnSe-ZnS composite was synthesized via one-step solvothermal process. XRD, FTIR, and Raman results confirmed the presence of mixed phases and corresponding molecular bonding of rutile TiO2, cubic ZnS, and orthorhombic SnSe. FESEM and TEM characterizations showed a unique interference between two distinguished morphologies, where TiO2 appeared as nanoflakes covering the spherical particles of ZnS/SnSe. XPS inspection of TiO2-modified SnSe-ZnS sample showed that small portion of the existed Zn2+ in tetrahedral sites is displaced into the octahedral sites as a result of the lattice distortion by incorporation of Ti4+/Ti3+ cations and oxygen deficiency in the structure. The initial specific discharge capacity for the modified SnSe-ZnS anode with 3% TiO2 was significantly increased from 770 to 805 mAh.g−1. The progressive cycling of the non-modified SnSe-ZnS anode possessed significant capacity fading, while the modified SnSe-ZnS anode with 3% TiO2 showed high capacity retention up to 100 mAh.g−1 after hundred cycles at 0.1 A.g−1. [ABSTRACT FROM AUTHOR]

In this paper, three different samples of spinel carbon@Sb2SnS4 (C@S) sulphide were successfully synthesized via simple hydrothermal technique using L-cysteine (L-cyst.), thioacetic acid (TAA) and thioacetamide (TAM) compounds as sulphur sources. Physical and surface characterizations for the synthesized sulphide powders, including X-ray diffraction (XRD), field emission electron microscope (FE-SEM), energy dispersive spectroscopy (EDS) and XPS techniques were carried out. The XRD results confirmed the formation of ternary sulphide Sb2SnS4 in the spinel cubic phase associated with graphite and minor phases of binary sulphides. The microstructure investigation of carbon-coated Sb2SnS4/TAA (C@S/TAA) revealed two-dimensional thin sheets collected as bundles that correspond to ternary sulphide phase, while small bright grains are related to the binary sulphides and oxides. Moreover, the existence of Sb3+ and Sn4+ was confirmed from the XPS double peaks of Sb3d and Sn3d orbitals. Galvanostatic cycling of the assembled cells indicated that C@S/TAA anode delivered the maximum discharge capacity of about 880 mA g−1, while the C@S/L-cyst. cell possessed the lowest discharge capacity of about 772 mAh g−1. Finally, the cell with C@S/TAA anode displayed the highest diffusion coefficient of Li+ ions and best rate capability performance due to the unique two-dimensional thin sheets-like morphology of Sb2SnS4 hybridized with carbon nanoplates. [ABSTRACT FROM AUTHOR]

In this study, the radiative parameters were acquired from the UV absorption spectra and the luminescence spectra of Er3+ ions doped Er2O3-Al2O3-Na2O-P2O5 glasses. The intensity of each absorption spectrum was utilized to deduce the radiative parameters and the parameters (Ω2, Ω4 and Ω6) of Judd-Ofelt theory. The FTIR and the elastic moduli of the quaternary glasses are also investigated. Analysis of the FTIR suggested that the presence of Er3+ ions created bridging oxygens and polymerized the local structure around atoms. This procedure manifested itself from decreasing the bond length of O-P and increasing the O/P ratio. The polymerization of the phosphate structure increased the ultrasonic velocity and the rigidity of the network. The electrical parameters of the phosphate glasses, such as the frequency and temperature dependence AC conductivity, dielectric loss and dielectric modulus were carried out. The Er3+ ions affected the carrier mobility by decreasing the electrical conductivity and increasing the activation energy. In addition, the frequency and temperature dependence of the dielectric modulus exhibited a Debye-type relaxation behavior. [ABSTRACT FROM AUTHOR]