A team of researchers at the Royal Melbourne Institute of Technology has developed a material that absorbs water vapor from the air, and then uses the energy of sunlight to split those water molecules into hydrogen and oxygen.
The material consists of a polymer of sulfur-rich molybdenum sulfides bonded to a layer of titanium oxide. The molybdenum compound absorbs water vapor from the air. The titanium oxide captures solar energy and turns it into electrical energy in a similar way to a photovoltaic cell. The electrical energy then splits the absorbed water molecules into hydrogen and oxygen.
Once the gases have escaped, the molybdenum sulfides absorbs another water molecule. In principle, the hydrogen and oxygen could be collected for use as fuel or to make other chemicals.
The material can be used as a paint but a mechanism needs to be developed to to separate the released hydrogen and oxygen gases.