From Fundamental Studies to Applied Research: SrIrO₃ as Efficient Electrocatalysts for Proton Exchange Membrane Electrolyzer

The search of efficient and stable electrocatalysts for oxygen evolution reaction (OER) in acidic electrolyte is the key to enable the commercialization of proton exchange membrane (PEM) electrolyzers and low hydrogen production price. However, there are few choices for such electrocatalysts due to the corrosive and oxidative conditions. As the discovery of SrIrO₃ as a new type of electrocatalysts in acidic OER, we have focused on the fundamental studies of mechanism that leads to its much better acitivity (~ 1000 times more) than the commercial standard, IrO₂. Using SrIrO₃ thin film epitaxially grown by molecular beam epitaxy (MBE) as the model system, we have studies the surface restructuring and Sr leaching in the reaction at the atomic scale. Later, using the learned knowledge, we design Ir less SrIrO₃-based catalysts in powder form that exhibit the same activity. We are currently extending our studies for this type of catalysts for general PEM electrolyzer applications.