Showing papers by "Ramanathan Arunachalam published in 2015"

Development of nano-spherical RuO2 active material on AISI 317 steel substrate via pulse electrodeposition for supercapacitors

Abstract: The goal of the present study is to develop a thin film hydrous ruthenium oxide (RuO2) electrode material on Ni flashed AISI 317 stainless steel (SS) substrate by pulse electrodeposition (PED) technique for application in supercapacitors. The nickel (Ni) strike thin film is deposited prior to RuO2 in order to improve the adhesion of the active material on the SS substrate. The prepared RuO2 active material on Ni strike SS electrode is characterized using XRD, SEM with EDAX and electrochemically using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) using an IVIUM reference potentiostat. The surface morphologies of the thin film (thickness of 2.3 μm) active materials are nano-spherical shaped and the particles are arranged uniformly without cracks on the SS substrate. The electrochemical impedance and CV profile demonstrates its superior characteristics in the electrochemical system. Moreover, the specific capacitance of RuO2 value is approximately 520 F g− 1 at the scan rate of 1 mV s− 1 and it's indicating a better utilization of active species in supercapacitors.

Electrochemical Influence of Nano-Spherical RuO2.xH2O Thin Film on Nickel Adhesion Layer as an Anode via Short-Time Pulse Current Technique for Energy Storage in Rechargeable Batteries

Abstract: A crystalline Sb–Cu alloy is investigated for use in Li-ion rechargeable batteries, and its structural, electrochemical and thermal properties are characterized. A pulse electrodeposition method is used to prepare Sb–Cu alloy film on Cu foil as a negative electrode. The structure of the alloy film electrode is characterized using XRD, FE-SEM and EDX. The electrochemical behavior of the Sb–Cu alloy film is investigated at the current rate of 0.1C to the cut-off potential range of 1.8 and 0.01 V vs. Li/Li+. Our experimental results demonstrate that the initial discharge capacity is 850 mAh g−1 and that the discharge capacity increases to 1034 mAh g−1 at the end of the 30th cycle with a stable cycle life. The Coulombic efficiency is approximately 83.5% with good cyclability. Moreover, the crystalline Sb–Cu alloy film has relatively low exothermic properties, and it may be an interesting candidate for use in the negative electrodes of Li-ion batteries.

Production of Metal Matrix Composite Using a Bottom Tapping Stir Casting Furnace

Abstract: Metal matrix composites (MMC's) have attracted the attention of researchers for quite some time. In the last 15 years, many studies have been reported in this field of MMC production through various routes. The most commonly used process for producing MMC is stir casting process whereby the reinforcement material is incorporated into the molten metal by stirring. It is a relatively low cost manufacturing process that is capable of producing high quality MMC. However, the process is associated with issues such as attaining uniform distribution of particles, wettability between particles and porosity in the MMCs. Because of these challenges, there has been continuous improvement in the process as well as the design of the furnace. In this research, an innovatively designed bottom tapping furnace has been used to produce the MMCs and the produced sample is characterized.