Something completely off topic yet...
Now where did I see this mechanism before? Who wants to bet that they've secured a patent on this method which has been prior art by mother nature since photosynthesis began?
Quote extracted from news brief at http://www.theregister.com/2004/08/13/green_fuel/
"A UK company has developed a nano-crystalline material that will dramatically improve the production of hydrogen by using solar energy to split water more efficiently into its elemental parts.
There are two photocatalytic cells arranged in series. The front cell is coated with a nano-crystaline film which absorbs high energy (ultraviolet and blue) light.
The lower energy light (green and red wavelengths) passes through the front cell and into the second. Here, the light excites the electrons in this cell's coating which sets up an electrical potential.
Now there is a potential difference between the two cells allowing current to flow. This electricity splits the water molecules in an electrolyte, producing hydrogen."