Abstract:
This research investigates the effects of electrode material, size and shape on hydrogen production
efficiency in electrolytic process. The electrolyzer comprises of electrodes submerged in 20%wt
potassium hydroxide solution and dc current is fed into the cell. The experimental work is divided
into three parts. Firstly stainless steel plated with nickel and copper are used as electrode material. It
is found that at the higher current density, the voltage and rate of hydrogen production are increased
whereas the efficiency is decreased. At the current density of 0.6 A/cm 2, the hydrogen production
rates are 0.82, 0.70 and 0.69 Llmin with 25.69, 20.01 and 19.12% efficiencies when using stainless
steel plated with nickel, stainless steel and copper, respectively. Second, Nickel plated stainless steel
plates with areas of 25, 50 and 100 cm2 are used as electrode. It is found that the hydrogen
production rate is maximum at 0.82 L/min with 26.06% efficiency at the current density of 0.6
Alcm2when using the 100 cm2 electrode. Finally, stainless steel plates with the area of 25 cm2 in
various shapes including rectangular, circular, diamond and haxagonal are used as electrodes. It has
been found that the hydrogen production rates and the efficiencies of the system at the same current
density are similar. The results show that stainless steel plated with nickel is the most suitable
electrode material for hydrogen production and the efficiency of hydrogen production increases
with the increasing electrode surface.