CONTEXT

The production of hydrogen by electrolysis met two major difficulties that limited the development of this technology. The first is the use of the platinum as cathode and iridium as anode.  These noble materials are deemed to be stable in acidic environment in aqueous solution where many metals are not. The use of these noble metals in catalytic quantity had great success for the hydrogen release. Despite only 0.02 mg of platinum per cm² of electrode, the technology could not be widely used due to the high price and annual production of platinum. The second difficulty was the low energy efficiency, which rarely exceeded 30%.