The best way to make hydrogen fuel is thought to be photo electrochemical, a process for water splitting. When the sun hits, the solar energy is absorbed in a cell used for splitting water molecules into hydrogen and oxygen.

Progress in the technology, however, has been limited by the lack of cheap catalysts. Platinum works, it's just too expensive and rare.

Now, scientists have found and tested an abundant and inexpensive catalyst — molybdenum sulfide — a necessary step on the road to the elusive clean, green hydrogen economy.

(READ the story in MSNBC.com)