The fundamental drivers of electrochemical barriers

Xi Chen; Georg Kastlunger; Andrew A. Peterson

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arXiv · 2306.05521

The fundamental drivers of electrochemical barriers

Xi Chen·Georg Kastlunger·Andrew A. Peterson

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Abstract

We find that ion creation/destruction dominates the behavior of electrochemical reaction barriers, through grand-canonical electronic structure calculations of proton-deposition on transition metal surfaces. We show that barriers respond to potential in a nonlinear manner and trace this to the continuous degree of electron transfer as an ion is created or destroyed. This explains both Marcus-like curvature and Hammond-like shifts. Across materials, we find the barrier energy to be driven primarily by the charge presented on the surface, which in turn is dictated by the native work function, a fundamentally different driving force than non-electrochemical systems.

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Xi Chen, Georg Kastlunger, Andrew A. Peterson. 2023-06-08. The fundamental drivers of electrochemical barriers. https://arxiv.org/abs/2306.05521

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