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Title: Revisiting trends in the exchange current for hydrogen evolution
Nørskov and collaborators proposed a simple kinetic model to explain the volcano relation for the hydrogen evolution reaction on transition metal surfaces such that j 0 = k 0 f (Δ G H ) where j 0 is the exchange current density, f (Δ G H ) is a function of the hydrogen adsorption free energy Δ G H as computed from density functional theory, and k 0 is a universal rate constant. Herein, focusing on the hydrogen evolution reaction in acidic medium, we revisit the original experimental data and find that the fidelity of this kinetic model can be significantly improved by invoking metal-dependence on k 0 such that the logarithm of k 0 linearly depends on the absolute value of Δ G H . We further confirm this relationship using additional experimental data points obtained from a critical review of the available literature. Our analyses show that the new model decreases the discrepancy between calculated and experimental exchange current density values by up to four orders of magnitude. Furthermore, we show the model can be further improved using machine learning and statistical inference methods that integrate additional material properties.  more » « less
Award ID(s):
1809085
PAR ID:
10417862
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
11
Issue:
20
ISSN:
2044-4753
Page Range / eLocation ID:
6832 to 6838
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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