الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Now, world is moving towards renewable energy as a clean and safe source of energy. But renewable energy sources have an irregular nature as they do not exist at any time. Thinking about storing energy to be used later on in isolated places or at where it is needed. There are many energy storage systems, including mechanical, thermal, chemical, electrochemical, and also electrical storage systems. Among electrical storage systems there are Supercapacitors, which have received considerable attention because of their higher power density and longer cycle life than batteries. At first manganese dioxide electrodes have been prepared as effective storage materials, which has been anodically electrodeposited on stainless steel substrate by two methods, a potentiostatic (PS) (in which the voltage is constant at 1V ) and the Galvanostatic (GS) (in which the current is constant at 1mA/cm2). After the preparation, characterizations for both structure and morphology were made using X-Ray diffraction (XRD) and Scanning electron microscopy (SEM), which showed that the electrodeposited MnO2 films were amorphous in nature. Also electrochemical measurements have been made using cyclic voltammetry (I-V), charge-discharge, electrochemical impedance spectroscopy, as well as measuring the cycle life. Potentiostatic deposited MnO2 film indicated enhancement of capacitive behavior than galvanostatic deposited MnO2 film. The potentiostatic deposited electrode exhibited an excellent cyclic stability with capacitance retention of 109 % after 1000 cycles by charging and discharging process at current density of 2 mA/cm2.
In the second part of the thesis, electrodes were prepared using anodically electrodeposited by the potentiostatic method and the electrodes were characterized in the sodium sulfate solution Na2SO4 as the electrolyte
solution at different concentrations of 0.1, 0.3, 0.5, 0.7, 1 Molar. The results of measurements showed that the 0.5 Molar electrolytic solution is the best concentration. This result was confirmed using many physical quantities such as the maximum specific capacitance, time constant, stored power, stored energy, And low resistance values.