O2‐Generation by Oxidation of Water with Di‐ and Trinuclear Ruthenium Complexes as Homogeneous and Heterogeneous Catalysts

The decomposition of water into O2 and H⊕ is an attractive process in many ways. The processes in a system consisting of ruthenium red (formula: [(NH3)5RuIIIORuIV(NH3)4ORuIII(NH3)5]Cl6) as catalyst. CeIV as oxidizing agent, and, where necessary, Kaolin as carrier, can be explained as follows: CeIV generates from ruthenium red a species that adds two H2O-molecules to give 1. Cleavage of H and formation of the OO bond leads to cyclic intermediates 2, which decomposes into O2 and ruthenium.