1, iron has no corrosion resistance, and it is easy to rust in electrolyte, which will affect the performance and life of water electrolyzer. Nickel has good corrosion resistance, which can resist the corrosion of electrolyte during electrolysis and prolong the service life of water electrolyzer.

2. The electrochemical activity of iron is low, which is not conducive to the reduction of water. Nickel has high activity and higher electrochemical activity, which can better promote the electrolytic reaction of water. Nickel is more suitable as the cathode material of water electrolyzer than iron, because it has higher electrochemical activity, better corrosion resistance and stability, can better promote the electrolytic reaction of water and improve the production efficiency of hydrogen.