Sorry, my bad. I thought photocatylitic water splitting occured naturally. After you questioned it I researched and learned it only occurs by artificial processes. Mea culp, mea culpa.
Photocatalytic water splitting is done biologically, but it’s a rare mutation. I’d look, because it’s around here somewhere, but it’s deeper in the FRchives than this oxygen thing is in the oceans. :^)
“Sorry, my bad. I thought photocatylitic water splitting occured naturally. “
In your post you referred to “Sunlight alone”. That is not photocatalytic water splitting.
Actually, the addition of a catalyze only speeds up a reaction. Sunlight can breakdown water but it is an extremely slow reaction.