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LiNi0.5Mn1.5O4 is a potential cathode material for 5 V batteries. This material was prepared by the solid-state redox method using nitrate and acetate based reactants. The precursor material was obtained when the mixture reactants was heated at 500° C for 10 hours and calcined at different temperatures in the range between 650 and 950° C for 12 hours. The structures of the synthesized materials were verified with X- ray diffraction (XRD) measurement and Scanning Electron Microscope (SEM). The charge-discharge technique was determined using Solartron 1470. As calcination temperature increases, the well-ordered crystal growth oriented to [1 1 1] direction shows a clear octahedral morphology, which is the characteristic of the typical cubic spinel. The Li/LiNi0.5Mn1.5O4 prepared from acetate based reactants calcined at 750° C for 12 h delivered the discharge capacity of 140 mAh/g. [ABSTRACT FROM AUTHOR]

Surface morphology study of Zinc Oxide (ZnO) thin films by using Thermal Chemical Vapor Deposition (Thermal-CVD) was investigated. The ZnO compound was synthesized from zinc acetate dehydrate which act as a starting material to form the ZnO thin films. It was deposited on as-prepared Nanonstructured Silicon (NSi) with deposition temperature ranging from 400–600° C without catalyst-assisted. The surface morphology of the samples before and after the deposition process was examined by using Analytical Scanning Electron Microscope (SEM). The result shows that the obtained ZnO thin films possess good crystalline structure at deposition temperature of 600° C and the surface morphologies of the ZnO thin films improved greatly with an increase in deposition temperature. XRD was employed to study the evolution of the crystalline orientation using X-Ray Diffractrometer (XRD). [ABSTRACT FROM AUTHOR]

The plasma sprayed hydroxyapatite (HA) coatings are used on metallic implants to enhance the bonding between the implant and bone in human body. The coating process was implemented at different spraying power for each spraying condition. The coatings formed from a rapid solidification of molten and partly molten particles that impact on the surface of substrate at high velocity and high temperature. The study was concentrated on different spraying power that is between 23 to 31 kW. The effect of different power on the coatings microstructure was investigated using scanning electron microscope (SEM) and phase composition was evaluated using X-ray diffraction (XRD) analysis. The coatings surface morphology showed distribution of molten, partially melted particles and some micro-cracks. The produced coatings were found to be porous as observed from the cross-sectional morphology. The coatings XRD results indicated the presence of crystalline phase of HA and each of the patterns was similar to the initial powder. Regardless of different spraying power, all the coatings were having similar XRD patterns. [ABSTRACT FROM AUTHOR]

Mechanism of doping of Mg in GaN thin film grown on c-plane sapphire substrate by plasma assisted-metalorganic chemical vapor deposition (PA-MOCVD) method have been investigated. The growth was carried out at temperature of 680 °C, which flow rate of Cp2Mg as dopant source was varied of 0.003; 0.006; 0.009 and 0.012 sccm. The Van der Pauw technique, X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize their electric, crystallographic and morphology properties. Hole concentrations of up to 1019 cm-3 have been observed for Mg-doped GaN films without any post-growth annealing. The XRD analysis showed change of the FWHMs for the (0002) orientation plane from Mg-doped GaN films. The difference of the atomic radius between Ga and Mg atoms causes lattice distortion in crystal. This lattice distortion generates dislocation and causes growth of the layer to be three-dimensional as showed on SEM images. [ABSTRACT FROM AUTHOR]