Dissociative Adsorption of Water at (211) Stepped Metallic Surfaces by First-Principles Simulations

Autor: Davide Donadio, Rengin Peköz
Rok vydání: 2017
Předmět:
Zdroj: The Journal of Physical Chemistry C. 121:16783-16791
ISSN: 1932-7455
1932-7447
DOI: 10.1021/acs.jpcc.7b03226
Popis: Steps at high-index metallic surfaces display higher chemical reactivity than close-packed surfaces and may give rise to selective adsorption and partial dissociation of water. Inspired by differential desorption experiments, we have studied the adsorption and dissociation of water clusters and one-dimensional wires on Pt(211) by density functional theory and molecular dynamics simulations. These calculations reveal that water at the step edges of Pt(211) adsorbs more weakly than at Pt(221), but partial dissociation of adsorbed water clusters is energetically competitive. We observe that the one-dimensional structure proposed experimentally can be realized only by partially dissociated water wires. In addition, weaker adsorption allows the formation of structures in which a number of water molecules detach from the step and form weak hydrogen bonds with the terrace. This study is further extended to the energetics of small water clusters on (211) surfaces of Ir, Rh, and Pd.
Databáze: OpenAIRE
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