Sara Oriani

Alumni

Water electrolysis is increasingly recognized as a sustainable method for producing green hydrogen, which plays a vital role in decarbonizing hard-to-abate sectors. This process consists of two primary half-reactions: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Among the catalysts explored for OER, iridium-based materials have gained significant attention due to their high catalytic activity and relative stability in acidic electrolytes, particularly in proton exchange membrane water electrolysis (PEMWE).However, the high cost of these electrocatalysts, along with other challenges, hampers the competitiveness of the technology. One critical issue is iridium dissolution, which can reduce the number of active sites and negatively impact the overall performance of the electrocatalyst. Therefore, it is essential to understand the mechanisms of iridium dissolution in acidic solutions to improve the durability of iridium-based catalysts.

The objective of my PhD research at Politecnico di Milano is to provide deeper insights into the degradation mechanisms of iridium, specifically examining the rates of dissolution and their effects on real-life operations. To accomplish this, I will investigate the influence of various stressors, including potential ranges, cycling frequency, and shut-down periods. Ultimately, my goal is to develop an accelerated stress test that enhances our understanding of these degradation mechanisms and informs effective mitigation strategies.