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Title: The Role of Ru Redox in pH-Dependent Oxygen Evolution on Rutile Ruthenium Dioxide Surfaces

Abstract

Rutile RuO 2 is known to exhibit high catalytic activity for the oxygen evolution reaction (OER) and large pseudocapacitance associated with redox of surface Ru, however the mechanistic link between these properties and the role of pH is yet to be understood. Here we report that the OER activities of the (101), (001) and (111) RuO 2 surfaces were found to increase while the potential of a pseudocapacitive feature just prior to OER shifted to lower potentials (“super-Nernstian” shift) with increasing pH on the reversible hydrogen electrode (RHE) scale. This behavior is in contrast to the (100) and (110) surfaces that have pH-independent Ru redox and OER activity. The link in catalytic and pseudocapacitive behavior illustrates the importance of this redox feature in generating active sites, building new mechanistic understanding of the OER.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361981
Report Number(s):
PNNL-SA-126478
Journal ID: ISSN 2451-9294
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chem; Journal Volume: 2; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Stoerzinger, Kelsey A., Rao, Reshma R., Wang, Xiao Renshaw, Hong, Wesley T., Rouleau, Christopher M., and Shao-Horn, Yang. The Role of Ru Redox in pH-Dependent Oxygen Evolution on Rutile Ruthenium Dioxide Surfaces. United States: N. p., 2017. Web. doi:10.1016/j.chempr.2017.04.001.
Stoerzinger, Kelsey A., Rao, Reshma R., Wang, Xiao Renshaw, Hong, Wesley T., Rouleau, Christopher M., & Shao-Horn, Yang. The Role of Ru Redox in pH-Dependent Oxygen Evolution on Rutile Ruthenium Dioxide Surfaces. United States. doi:10.1016/j.chempr.2017.04.001.
Stoerzinger, Kelsey A., Rao, Reshma R., Wang, Xiao Renshaw, Hong, Wesley T., Rouleau, Christopher M., and Shao-Horn, Yang. 2017. "The Role of Ru Redox in pH-Dependent Oxygen Evolution on Rutile Ruthenium Dioxide Surfaces". United States. doi:10.1016/j.chempr.2017.04.001.
@article{osti_1361981,
title = {The Role of Ru Redox in pH-Dependent Oxygen Evolution on Rutile Ruthenium Dioxide Surfaces},
author = {Stoerzinger, Kelsey A. and Rao, Reshma R. and Wang, Xiao Renshaw and Hong, Wesley T. and Rouleau, Christopher M. and Shao-Horn, Yang},
abstractNote = {Rutile RuO2 is known to exhibit high catalytic activity for the oxygen evolution reaction (OER) and large pseudocapacitance associated with redox of surface Ru, however the mechanistic link between these properties and the role of pH is yet to be understood. Here we report that the OER activities of the (101), (001) and (111) RuO2 surfaces were found to increase while the potential of a pseudocapacitive feature just prior to OER shifted to lower potentials (“super-Nernstian” shift) with increasing pH on the reversible hydrogen electrode (RHE) scale. This behavior is in contrast to the (100) and (110) surfaces that have pH-independent Ru redox and OER activity. The link in catalytic and pseudocapacitive behavior illustrates the importance of this redox feature in generating active sites, building new mechanistic understanding of the OER.},
doi = {10.1016/j.chempr.2017.04.001},
journal = {Chem},
number = 5,
volume = 2,
place = {United States},
year = 2017,
month = 5
}
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