Adsorption and Diffusion of H Atoms on beta-PtO2 Surface: The Role of Nuclear Quantum Effects

TL;DR

This study uses first-principles calculations to explore how hydrogen atoms adsorb and diffuse on beta-PtO2 surfaces, highlighting the importance of nuclear quantum effects especially at low temperatures.

Contribution

It reveals the significant role of nuclear quantum effects in hydrogen diffusion on beta-PtO2, a factor often neglected in surface diffusion studies.

Findings

H prefers top O sites for adsorption

Energy barriers are similar to H diffusion on Pt(111)

Nuclear quantum effects dominate at cryogenic temperatures

Abstract

The adsorption and diffusion of H atoms on beta-PtO2(001) surface have been studied using first-principles calculations. The chemisorbed H atoms are found to bind preferentially on the top sites of O atoms due to the much larger adsorption energies with comparison to adsorption atop Pt atoms. The calculated energy barriers along the optimal diffusion paths are comparable with that of H diffusion on Pt(111). Within the WKB approximation, the nuclear quantum effects (NQEs) along the diffusion paths are investigated. It turns out that the NQEs are significant for the surface diffusion of H at room temperature and play a dominant role in cryogenic conditions.