Catalysis

High-entropy oxides for the oxygen evolution reaction

Authors

Abstract

High-entropy oxides are oxides consisting of five or more metals incorporated in a single lattice, and the large composition space suggests that properties of interest can be readily optimised. For applications within catalysis, the different local atomic environments result in a distribution of binding energies for the catalytic intermediates. Using the oxygen evolution reaction on the rutile (110) surface as example, here we outline a strategy for the theoretical optimization of the composition. Density functional theory calculations performed for a limited number of sites are used to fit a model that predicts the reaction energies for all possible local atomic environments. Two reaction pathways are considered; the conventional pathway on the coordinatively unsaturated sites and an alternative pathway involving transfer of protons to a bridging oxygen. An explicit model of the surface is constructed to describe the interdependency of the two pathways and identify the composition that maximizes catalytic activity.

Content

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Supplementary material

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Electronic supplementary information
Computational details, additional details of the fitting procedure and the composition optimization model.