Tiny titanium barrier halts big problem in fuel-producing solar cells

What if we could turn sunlight and water into fuel? That’s the idea behind certain types of solar cells. Known as dye-sensitized photoelectrochemical cells, these devices use the energy contained in sunlight to split water into hydrogen and oxygen. Hydrogen itself can be used as a fuel, or it can be used to make other types of fuels. The problem? The conditions necessary to split water tend to damage the solar cell. Now, researchers have designed a more stable dye-sensitized photoelectrochemical cell.