In hydrogen - oxygen fuel cell, the electrode used is carbon electrode.Hydrogen is passed through through the anode compartment where it is oxidised. Oxygen is passed through the cathode compartment where it is reduced.During oxidation, the electrons lost by hydrogen flows through the carbon electrode and reaches the cathode compartment where they are used up by the oxygen to yield Hydroxide ion. My question is , what is the mechanism behind the electron flow through the carbon electrode?
Carbon is a fairly good electrical conductor. Its use as an electrode in electrochemical cells has a long history.