Surface Orientation Dependent Water Dissociation on Rutile Ruthenium Dioxide

Reshma R. Rao*, Manuel J. Kolb, Jonathan Hwang, Anders Pedersen, Apurva Mehta, Hoydoo You, Kelsey A. Stoerzinger, Zhenxing Feng, Hua Zhou, Hendrik Bluhm, Livia Giordano, Ifan E. L. Stephens, Yang Shao-Horn

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

97 Downloads (Pure)

Abstract

Rutile RuO2 is a highly active catalyst for a number of (electro)chemical reactions in aqueous solutions or in humid environments. However, the study of the interaction of RuO2 surfaces with water has been confined largely to the ultra-high vacuum environment, and to the thermodynamically stable (110) surface. In this work, we combine ambient pressure X-ray photoelectron spectroscopy, in situ surface diffraction and density functional theory calculations to investigate how four different facets of RuO2 interact with water under humid and electrochemical environments. The vacant coordinatively unsaturated Ru site (CUS) allows for the adsorption and dissociation of water molecules. Different surfaces exhibit unique binding energetics for -H2O and -OH and can allow for different degrees of hydrogen bonding between the adsorbates. Consequently, the degree of water dissociation is found to be sensitive to the surface crystallographic orientation - being maximum for the (101) surface, followed by the (110), (001) and (100) surfaces. This study identifies crystallographic orientation as an important parameter to tune not only the density of active sites but also the energetics for water dissociation; this finding is of great significance for many catalytic reactions, where water is a key reactant, or product.
Original languageEnglish
JournalJournal of Physical Chemistry C
Volume122
Issue number31
Pages (from-to)17802-17811
Number of pages10
ISSN1932-7447
DOIs
Publication statusPublished - 2018

Fingerprint

Dive into the research topics of 'Surface Orientation Dependent Water Dissociation on Rutile Ruthenium Dioxide'. Together they form a unique fingerprint.

Cite this