[typhonic]

In 1973 I visited the office of a chemistry professor. He and his research partner seemed to be on somewhat of a downhill slide. For years they had dreams of discovering a catalyst that would let water break into hydrogen and oxygen from exposure to direct sunlight. They never found that catalyst, and after nearly fifty years, I never even hear the concept any more.

[taneq]

Looks like it's still an active area of research (the catalyst bit, not necessarily the sunlight bit): https://www.chemistryworld.com/news/ideal-water-splitting-ca...