(667f) An Ab-Initio Molecular Dynamics Study of the Metal-Water Interface for ORR Activity in Alkaline Media.

The oxygen reduction reaction (ORR) is an important process for electrocatalysis, particularly in fuel cells. The metal-water interface is a crucial factor that affects the efficiency of the ORR process, particularly in alkaline media where water is a reactant, making it challenging to determine the proton-electron transfer (PET) barrier.

Recently, a method for calculating the PET barrier has been proposed, which combines bond order conservation, EVB theory, and Marcus theory [1]. This approach allows for an accurate and efficient calculation of electron transfer kinetics. In this study, we apply this method to analyze the ORR kinetics on Pt(111) surfaces in alkaline media. Using density functional theory (DFT) calculations and ab-initio molecular dynamics (AIMD) simulations, we investigate the ORR kinetics on Pt(111) surfaces by considering the changes in coverage with respect to the potential. We observe the ORR kinetic changes in each region and elucidate the mechanism. Our study reveals the importance of the dynamic fluctuation of solvent water molecules at room temperature, which significantly affects the ORR kinetics. Our findings provide a more precise theoretical rate and demonstrate the importance of understanding the metal-water interface in electrocatalytic processes, particularly in alkaline media, which can guide the design of efficient electrocatalysts for various technological applications.

[1] J. Am. Chem. Soc. 2021, 143, 19341−19355