As the chemical process industry continues its path towards decarbonization, improving the economic competitiveness of electrochemical alternatives to legacy thermochemical processes is gaining increasing interest. In particular, water electrolysis offers a promising solution to significantly reduce carbon emissions in H2-intensive processes. However, industrial-scale electrolyzers largely use alkaline electrolysis despite acidic polymer electrolyte membrane (PEM) electrolyzers showing better performance, since PEM electrolyzers are hindered by the high cost and anodic corrosion of precious metal catalysts like Ir and Ru. Of the possible anodic catalysts, IrO2 is the most stable but still corrodes at the high overpotentials necessary for industrial-level current densities via a poorly understood amorphization and dissolution process. While efforts have been made to explain and predict experimental oxygen evolution reaction (OER) activity trends, stability challenges, which are crucial for device lifetime and economic viability, have been largely overlooked. To achieve Department of Energy targets of reducing the cost of green H2 from ~$5/kg to ~$1-2/kg, it is crucial to gain atomic-level insights into how IrO2 catalyzes the OER and concomitant dissolution processes. Here, we present a novel computational reference electrode which enables facile determination of corrosion thermodynamic driving forces on a range of doped and undoped rutile oxide surfaces. Utilizing this development, we identify structure-property relationships controlling activity and stability trends on rutile oxides. We find that, depending on local electronic structure perturbation, OER activity and corrosion are likely not intrinsically coupled. Instead, while electronic structure predictors for the two reactions are weakly correlated, they are fundamentally distinct. Our findings pave the way towards development of PEM electrolyzer anodes with enhanced stability without compromising activity – an important step towards meeting federal green H2 price targets.
