Processing of Prussian Blue-type Oxygen Evolution Electrocatalysts

Water oxidation is considered the bottleneck in the development of an efficient and cost-effective water splitting technology. State-of-the-art water electrolyzers are still far from being competitive with steam reforming, the... [ view full abstract ]

Water oxidation is considered the bottleneck in the development of an efficient and cost-effective water splitting technology. State-of-the-art water electrolyzers are still far from being competitive with steam reforming, the cheap and well-established hydrogen production scheme from fossil fuels. One of the challenges resides in substituting the expensive noble metal catalysts by earth-abundant counterparts while maintaining the efficiency and performance required for technological applications. Inexpensive transition metal oxides are very competitive catalysts for the oxygen evolution reaction (OER) but exclusively in alkaline media. We have discovered in our labs the unparalleled OER activity offered by Prussian blue analogues. These coordination polymers are robust in the solid state, stable and active in a large pH range (0 < pH < 11), appearing as a unique alternative based on abundant and inexpensive metals. In this communication, we will present our latest results and advances in the processing of these coordination networks for their implementation into water splitting devices.