Photoelectrochemical water oxidation reaction for coated and meta-chemical surface electrodes with Na₃[Ru₂(μ-CO₃)₄]

The most economical and efficient method to produce green hydrogen relies on electrochemistry, the electricity for which is of a green origin, and on photocatalytic water splitting. The latter technology involves the use of a photocatalyst or a photo-electrocatalyst to transform solar energy into chemical energy. Vast efforts have thus been dedicated to the pursuit of such a catalyst. The current study focused on the development of a heterogeneous photoelectrochemical system in which the Na₃[Ru₂(μ-CO₃)₄] complex was used as a WOC. To that end, two types of electrodes were prepared: coated indium tin oxide (ITO) and meta-chemical surface (MCS) electrodes. Under 420 nm illumination, both electrode types exhibited higher catalytic currents than were observed without light. Our novel application of the Na₃[Ru₂(μ-CO₃)₄] complex as a catalyst in the photoelectrochemical water oxidation reaction requires minute amounts of the complex. The study findings add to the knowledge about the water-splitting process, and ultimately, they may facilitate the broader adoption of hydrogen as an environmentally friendly and increasingly accessible energy source.