Tuning Fundamental Properties of Ir-Based Materials to Enhance Their Electrocatalytic Performance in the Oxygen Evolution Reaction

摘要

The oxygen evolution reaction (OER) underpins electrochemical technologies for hydrogen generation. The sluggish kinetics of the OER and the instability of most of the anode materials hinder widespread application of proton exchange membrane water electrolyzers (PEMWE). Up to now, only iridium-based catalysts meet the necessary requirements and are currently employed in PEMWE. Despite the scarcity and high cost of iridium, its relatively high reactivity and superior stability make it irreplaceable to optimize the durability of the electrolyzer. Understanding what governs the electrocatalytic activity as well as the long-term stability of iridium is crucial for the development of novel catalysts that will enable efficient energy conversion and storage technologies. Gaining this knowledge requires establishing the correlation between the atomic-scale structure of the catalysts, their electronic properties and the mechanisms of the OER and other side reactions that lead to the material's degradation.