Peter Lobner
Splitting water (H2O) is the process of splitting the water molecule into its constituent parts: hydrogen (H2) and oxygen (O2). A catalyst is a substance that speeds up a chemical reaction or lowers the energy required to get a reaction started, without being consumed itself in a chemical reaction.
Water molecule. Source: Laguna Design, Getty Images
A new catalyst, created as a thin film crystal comprised of one layer of iridium oxide (IrOx) and one layer of strontium iridium oxide (SrIrO3), is described in a September 2016 article by Umair Irfan entitled, “How Catalyst Could Split Water Cheaply.” This article is available on the Scientific American website at the following link:
The new catalyst, which is the only known catalyst to work in acid, applies to the oxygen evolution reaction; the slower half of the water-splitting process.
Author Irfan notes that, “Many of the artificial methods of making hydrogen and oxygen from water require materials that are too expensive, require too much energy or break down too quickly in real-world conditions…” The availability of a stable catalyst that can significantly improve the speed and economics of water splitting could help promote the shift toward more widespread use of clean, renewable fuels. The potential benefits include:
- May significantly improve hydrogen fuel economics
- May allow water splitting to compete with other technologies (i.e., batteries and pumped storage) for energy storage. See my 4 March 2016 posting on the growing need for grid energy storage.
- May improve fuel cells
At this point, it is not clear exactly how the IrOx / SrIrO3 catalyst works, so more research is needed before the practicality of its use in industrial processes can be determined.
The complete paper, “A highly active and stable IrOx/SrIrO3 catalyst for the oxygen evolution reaction,” by Seitz, L. et al., is available to subscribers on the Science magazine website at the following link: