2023 AIChE Annual Meeting

(521ao) Strain-Dependent Activity and Stability of RuO2 and IrO2 Oxygen Evolution Catalysts.

Authors

Alexandrov, V., University of Nebraska-Lincoln, NE, USA
The development of active and stable electrocatalysts is crucial for energy conversion technologies such as water electrolysis and fuel cells. Strain engineering is a promising approach to modulate the electrocatalytic activity of materials, which is done by tuning the lattice strain to optimize the catalytic performance. However, the role of strain on the electrochemical stability of catalysts is not yet well understood.

The oxygen evolution reaction (OER) is an important part of sustainable hydrogen production via water electrolysis. Rutile RuO2 and IrO2 are widely used electrocatalysts for OER due to their high activity and stability, which are critical factors for efficient and durable electrochemical devices.

In this study, we investigate the effects of compressive and tensile strain on both the activity and stability of rutile RuO2 and IrO2 for OER. We combine ab initio thermodynamics and molecular dynamics (AIMD) simulations to examine the effects of strain on OER mechanisms and the correlation between activity and stability in noble metal oxides. Specifically, we focus on the electronic structure descriptors to explain the obtained results.

Furthermore, we evaluate the activation barriers for transition-metal dissolution from RuO2 and IrO2 via AIMD simulations. The computational results will be discussed in light of available experimental data to provide new insights into the role of strain in electrocatalytic activity and stability.