Passing current through water splits it into hydrogen and oxygen gas — doing this directly in seawater skips a costly freshwater purification step.
2H2O -> 2H2 + O2 (cathode/anode)
rate ~ j * A_electrode
- Water molecules — seawater molecules present at the electrode surfaces.
- Electrode sites — catalytic electrode surface patches where the splitting reaction occurs.
- Current density — applied electrical current per unit electrode area, the main driver of gas output.
- Electrolyte conductivity — how well seawater's dissolved salts conduct current between electrodes.
Seawater electrolysis avoids competing with freshwater supplies for green-hydrogen production, a major advantage for coastal desert regions building hydrogen export industries.