Effect of a humid environment on the surface structure of RuO2(110)

TL;DR

This study uses density-functional theory and thermodynamics to analyze how humid environments influence the surface structure of RuO2(110), revealing that even low hydrogen levels stabilize oxygen-rich surface terminations.

Contribution

It provides a comprehensive phase diagram of RuO2(110) surface structures in water vapor, highlighting the stabilizing effect of hydrogen on surface terminations.

Findings

Hydrogen stabilizes oxygen-rich surface structures.

Water vapor influences surface phase stability.

Hydroxyl groups form at low hydrogen concentrations.

Abstract

Combining density-functional theory and thermodynamics we compute the phase diagram of surface structures of rutile RuO2 (110) in equilibrium with water vapor in the complete range of experimentally accessible gas phase conditions. Through the formation of hydroxyl or water-like groups, already lowest concentrations of hydrogen in the gas phase are sufficient to stabilize an oxygen-rich polar oxide termination even at very low oxygen pressure.