This seems like an incredibly complex way to do something very simple: http://news.yahoo.com/sustainable-energy-breakthrough-hydrogen-fuel-sunlight-140037620.html Why not just hook up some solar cells to two wires and dip them in salt water? Hydrogen gas forms at the cathode and oxygen forms at the anode. I used to collect them in test tubes when I was a kid and make cool mini-explosions with the hydrogen.