First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface
Abstract
The binding of hydrogen on Ni(111) in the presence of an water is considered using both a bilayer and a saturated model of the solvent environment. The presence of a water bilayer did not change the binding energies or geometry of hydrogen on the Ni(111) compared to adsorption in ultra-high vacuum. Using the saturated model (four bilayers over the surface) we also monitored the change in hydrogen binding as a function of electrochemical potential. Binding energies for hydrogen at the hcp and octahedral sites shifted endothermically as the potential was made more anodic, indicating that reductive partial charge transfer occurs. Binding at the tetrahedral site was found to be partially oxidizing. Calculation of vibrational modes allowed the extrapolation of ab initio results to ambient and elevated temperatures. Surface Pourbaix diagrams were constructed illustrating the stability of various phases on the Ni(111) surface as a function of pH and potential.
- Authors:
- Publication Date:
- Research Org.:
- Knolls Atomic Power Laboratory (KAPL), Niskayuna, NY
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 875455
- Report Number(s):
- LM-05K159
TRN: US200605%%20
- DOE Contract Number:
- DE-AC12-0039357
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 08 HYDROGEN; 42 ENGINEERING; ADSORPTION; EXTRAPOLATION; GEOMETRY; HYDROGEN; SOLVENTS; STABILITY; WATER
Citation Formats
C Taylor, R Kelly, and M Neurock. First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface. United States: N. p., 2005.
Web. doi:10.2172/875455.
C Taylor, R Kelly, & M Neurock. First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface. United States. doi:10.2172/875455.
C Taylor, R Kelly, and M Neurock. Mon .
"First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface". United States.
doi:10.2172/875455. https://www.osti.gov/servlets/purl/875455.
@article{osti_875455,
title = {First Principles Calculations of Electrochemically Controlled Hydrogen Mobility and Uptake at the Ni(111)H2O Interface},
author = {C Taylor and R Kelly and M Neurock},
abstractNote = {The binding of hydrogen on Ni(111) in the presence of an water is considered using both a bilayer and a saturated model of the solvent environment. The presence of a water bilayer did not change the binding energies or geometry of hydrogen on the Ni(111) compared to adsorption in ultra-high vacuum. Using the saturated model (four bilayers over the surface) we also monitored the change in hydrogen binding as a function of electrochemical potential. Binding energies for hydrogen at the hcp and octahedral sites shifted endothermically as the potential was made more anodic, indicating that reductive partial charge transfer occurs. Binding at the tetrahedral site was found to be partially oxidizing. Calculation of vibrational modes allowed the extrapolation of ab initio results to ambient and elevated temperatures. Surface Pourbaix diagrams were constructed illustrating the stability of various phases on the Ni(111) surface as a function of pH and potential.},
doi = {10.2172/875455},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Nov 14 00:00:00 EST 2005},
month = {Mon Nov 14 00:00:00 EST 2005}
}
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