Photo-induced water oxidation with tetra-nuclear ruthenium sensitizer and catalyst: A unique 4 x 4 ruthenium interplay triggering high efficiency with low-energy visible light

The combined use of a tetranuclear Ru(II) dendrimeric photosensitizer (1) and of a tretraruthenium substituted polyoxotungstate (2) as the catalyst enables photo-induced water oxidation at 550 nm producing O(2) with an outstanding quantum yield of 0.30.