Development status and prospect of low iridium catalysts for hydrogen production by PEM electrolysis

With the rapid development of green renewable energy, proton exchange membrane (PEM) hydroelectrolysis technology has attracted much attention as a key link between renewable energy and hydrogen energy. In this paper, the working principle and technical status of anodes in PEM electrolyzers and the research progress of low iridium catalysts are reviewed. Even though PEM electrolysis technology has broad prospects, but the scarcity and the high price of iridium using in anode catalyst restrict the popularization of PEM electrolysis technology. The research of low iridium oxygen evolution (OER) catalysts with high activity and stability becomes much more important for the development of PEM electrolysis technology. At present, the low iridium catalysts mainly focus on the doped and supported catalysts. These two types of low iridium catalysts show higher catalytic activity than iridium oxides. Several low iridium catalysts reported recently, such as double perovskite, GD-doped IrO2, IrNiOx with core-shell structure, IrOx/ATO etc., are described in this paper. The main challenges for increasing the activity and stability of low iridium catalysts are summarized, such as the crystal phase instability of doped catalysts and the utilization of Ir in supported catalysts. Finally, some suggestions and prospects are summarized in order to promote the activity and stability of low iridium catalysts supporting the future development of PEM electrolysis technology. © 2025 Chemical Industry Press Co., Ltd.. All rights reserved.