Authors: Martinez-Huerta, MV
The electrochemical reactions of oxygen reduction and evolution are fundamental for the development of electrochemical devices for the conversion and storage of renewable energy such as electrolysers, fuel cells and regenerative fuel cells. The hydrogen would be generated from the electrolysis of water when there is excess of energy, and the fuel cell generates electricity when the demand increases and stored hydrogen is available. If both stacks are combined into a single unit, the cell is called unitized regenerative fuel cell, where only one of the two modes (electrolyser or fuel cell) can be operated at one time. Research and development efforts are currently focused on obtaining electrocatalysts capable of reducing oxygen and oxidising water, both in terms of efficiency (high overpotentials) and durability (aggressive degradation conditions)..