Hydrogen–Oxygen Fuel Cell
A fuel cell in which hydrogen is oxidised at the anode and oxygen reduced at the cathode, producing only water.
Formula / equation
2H₂ + O₂ → 2H₂O, E° = 1.23 V
Unit
V
In depth
Platinum catalysts on a proton-exchange membrane allow the reaction to proceed at low temperature. The only emission at point of use is water, though the overall environmental benefit depends entirely on how the hydrogen was produced in the first place.
Examples in the real world
Fuel cell vehicles; the Apollo missions, where the product water was drunk by the astronauts.