THE EFFECT OF GRID ELECTRODE STRUCTURE AND SURFACE AREA OF ELECTRODE ON PERFORMANCE OF ALKALINE WATER ELECTROLYSIS

Abstract

The electrolysis cell is constructed to study I-V characteristic of electrodes with electrolyte (1M NaOH). In addition, current verses input power (Pin) and resistance verses voltage curve of the cell is also study, at difference fixed grid voltage. The I-V Characteristic of electrodes show reaction is not started (that is not current observed) at low applied voltage but with increasing the voltage reaction started linearly for both small and large grid window size. The input power for both small and large grid window increase linearly. The resistance of cell goes decrease with grid voltage increase, decrease with increase grid voltage and become constant with increase grid voltage for anode, cathode and grid electrodes respectively for both windows. Moreover the excremental observed value for hydrogen production is higher than theoretical value, which is an error but minimum for both windows. The efficiency of hydrogen with the help of current and voltage at different electrodes are about 68%. This may be due to the concentration of electrolyte, nature of electrode materials and system constructed. With increase the surface area of grid electrode then increase the hydrogen production rate. This is because large surface area goes to contact with large number of electrolyte molecules and the production of hydrogen depend up on this contact i.e. larger surface area has large number of reaction. Therefore the productions of hydrogen gas depend upon the surface area of grid. Grid voltage increases and cathode current Ic is also increases with input power pin. Thus, in general one can say with increasing the grid voltage cell resistance decrease. The resistance of cell decrease sharply in between 0.5V to 1.0V with grid voltage while seen almost constant beyond 3.5V.