In Germany, the HZB Institute for Solar Fuels and TU Delft University of Technology have created a solar device that can split water into hydrogen cheaply and efficiently. On the solar cell, the anode is made from metal oxide bismuth vanadate (BiVO4) plus a small amount of tungsten atoms with a dash of wolfram atoms thrown in for good measure.
According to HZB, “Thus the experts were able to develop a rather elegant and simple system for using sunlight to split water into hydrogen and oxygen. This process, called artificial photosynthesis, allows solar energy to be stored in the form of hydrogen. The hydrogen can then be used as a fuel either directly or in the form of methane, or it can generate electricity in a fuel cell.
“One rough estimate shows the potential inherent in this technology: At a solar performance in Germany of roughly 600 Watts per square meter, 100 square meters of this type of system is theoretically capable of storing 3 kilowatt hours of energy in the form of hydrogen in just one single hour of sunshine. This energy could then be available at night or on cloudy days.”
The scientists found out that bismuth vanadate works much better than other metal oxides in splitting water. The process of producing the solar cell is a bit complex but the materials are cheap and the results efficient, so this could be the Next Big Thing in hydrogen production (or at least one of many next big things).