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LiNi0.8Co0.2O2 is a promising candidate to replace LiCoO2. The present paper describes the preparation of LiNi0.8Co0.2O2 compounds from nitrate sources and sucrose (or sugar) by the sucrose combustion process (SCP), which involves application of a conventional combustion method. In the proposed approach, sucrose serves as a fuel, a dispersing agent, and a precipitation suppressant. Precursors were made via a combustion reaction, and LiNi0.8Co0.2O2 was subsequently synthesized by heat treatment at 800 °C for 16 h in oxygen atmosphere. The initial discharge capacity was 175 mA h/g when a cell was operated at 2.7–4.3 V at 0.5 C-rate. Furthermore, it shows good cycling stability. When increased amount of sucrose were added as a start material, the final calcined powder displayed smaller particle size and better discharge capacity. It is expected that optimization of the heat treatment conditions would yield LiNi0.8Co0.2O2 with excellent properties. Furthermore, SCP is expected to be applicable to the production of various materials. Keywords: Lithium batteries, Cathode materials, LiNi0.8Co0.2O2, Sucrose combustion, Combustion method

This study reports the enhanced electrical properties of InGaZnO 4 thin film transistors (TFTs) with sputter-deposited poly(methyl methacrylate) (PMMA)/Ba 0.6 Sr 0.4 TiO 3 (BST) stacked gate dielectrics. A noticeable reduction in the leakage current density (∼10 -8 A/cm 2 at 0.3 MV) was achieved by coating a PMMA overlayer. The InGaZnO 4 TFTs utilizing the PMMA (30 nm)/BST (270 nm) stacked gate dielectrics exhibited a high on/off current ratio of 2.6 × 10 6 , a high field effect mobility of 10.2 cm 2 /V · s, and a low threshold voltage of 1.1 V. Using stacked gate dielectric layers, we realized the low voltage operating InGaZnO 4 TFTs on a poly(ethylene terephthalate) substrate.

The facile synthesis, by electrospinning of highly conductive RuO2 fiber mats as the conducting core of electrochemical capacitors, is reported. Electrospun RuO2 fiber mats, calcined at 400 °C, exhibited highly porous morphologies composed of crystalline RuO2 nano-particles with an average particle size of 10 nm. The highly conducting (σ = 288 S cm−1) fiber mats were used as the basis of a hybrid electrochemical capacitor in which the fiber mats served as the conducting core for electrochemically deposited hydrate RuO2·nH2O overlayers. These electrochemical capacitors exhibited superior characteristics: a high specific capacitance of ∼886.9 F g−1 (based on the mass of the hydrous RuO2 coating layer) at scan rate of 10 mV s−1 and high rate capability with a capacity loss of only 30% from 10 to 2000 mV s−1. This is attributed to the superior electron transport pathways provided by the fiber mat core to the upper ionically conducting hydrous RuO2 coating layer.

The Ge 1-x Te x chalcogenide thin films for phase change memory applications were prepared on TiAIN (30 nm)/ SiO 2 (100 nm)/Si substrates by metallorganic chemical vapor deposition (MOCVD) using Ge(allyl)4(Ge(C3H5)4), Sb(iPr) 3 (Sb(C 3 H 7 ) 3 ), and Te(tBu) 2 (Te(C 4 H 9 ) 2 ) precursors. The Ge 1-x Te x films were grown by the tellurium deposition at 230-250°C on Ge films deposited on a TiAIN electrode in the presence of Sb at 370°C. The Ge 1-x Te x film growth by the tellurium deposition on Ge films depends on both the tellurium deposition temperature and the deposition time. The Ge and Te in the films deposited on a confined structure of 500 nm in diameter and 200 nm in depth shows a homogeneous distribution, and their distribution was consistent with the films deposited on a planar structure.

We investigated the indium doping effects on ZnO thin film using radio frequency (rf) magnetron sputtering and rapid thermal annealing. The structural and electrical properties of indium doped ZnO thin films were measured by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and Hall effect measurement. Thin films were deposited at a high temperature of 800°C in order to improve the crystal quality and were annealed for a short time of only 3 min, sufficient time to activate the dopants. The structural properties of undoped and indium doped films were considerably improved with increasing oxygen gas in plasma. Indium doping also significantly increased the electron concentration, making the films heavily n-type. However, the crystallinity and surface roughness of the films degraded and the mobility decreased with increasing indium doping content, likely as a result of the formation of smaller grain size. From this study, on the basis of the structural and electrical properties of fabricated film, the best electrical properties have been obtained for 0.3 atom % indium doped ZnO thin film. This thin film, with a similar crystalline structure to undoped ZnO films, which presents the electron concentration of 1.296 X 10 19 cm -3 , resistivity of 0.0121 Ω cm and mobility of 39.71 cm 2 /V s, can be considered for application to light emitting diodes.