Electrolysis is an old technology, first observed during the early 1800s [1]. Electrolysis is the process of splitting water through the use of electricity into its elements: hydrogen and oxygen. In order to conduct electricity, water requires an electrolyte. The most commonly used electrolyte in industry is potassium hydroxide. A basic electrolyte is not necessary. Acidic electrolytes generate corrosion in a more uncontrolled manner, therefore basic electrolytes are the choice for industry [2]. The basic half reaction are shown in the figure below. The acidic half reactions that occur at each electrode are different, however the overall reaction is the same. Although electrolysis only comprises approximately 5% of world hydrogen production, it is a commercially viable renewable production method [2]. Currently, the cost of electricity is prohibitive in expanding the scope of this technology.

[1] Wendt, H., 1990, Electrochemical Hydrogen Technologies: Electrochemical Production and Combustion of Hydrogen, Elsevier Science Publishers B.V., The Netherlands.

[2] Jones, R.H., Thomas, G.J., 2008, Materials for the Hydrogen Economy, CRC Press, Florida.