Ab Initio Thermodynamic Modeling of Electrified Metal鈥揙xide Interfaces: Consistent Treatment of Electronic and Ionic Chemical Potentials

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• 作者：Zhenhua Zeng ; Martin Hangaard Hansen ; Jeffrey P. Greeley ; Jan Rossmeisl ; M氓rten E. Bj枚rketun
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：October 2, 2014
• 年：2014
• 卷：118
• 期：39
• 页码：22663-22671
• 全文大小：462K
• ISSN：1932-7455

文摘

Solid oxide fuel cells are attractive devices in a sustainable energy context because of their fuel flexibility and potentially highly efficient conversion of chemical to electrical energy. The performance of the device is to a large extent determined by the atomic structure of the electrode鈥揺lectrolyte interface. Lack of atomic-level information about the interface has limited the fundamental understanding, which further limits the opportunity for optimization. The atomic structure of the interface is affected by electrode potential, chemical potential of oxygen ions, temperature, and gas pressures. In this paper we present a scheme to determine the metal鈥搊xide interface structure at a given set of these environmental parameters based on quantum chemical calculations. As an illustration we determine the structure of a Ni-YSZ anode as a function of electrode potential at 0 and 1000 K. We further describe how the structural information can be used as a starting point for accurate calculations of the kinetics of fuel oxidation reactions, in particular the hydrogen oxidation reaction. More generally, we anticipate that the scheme will be a valuable theoretical tool to describe solid鈥搒olid electrochemical interfaces.