Facilitating the Rational Design of Active Sites for the Oxygen Evolution Reaction on 3d Transition Metal Oxide Catalysts
Final Report Abstract
The project aims at developing new modeling methods for the electrocatalytic activity of the Oxygen Evolution Reaction (OER) on 3d transition metal oxides (TMOs) with a special focus on an accurate kinetic description, an incorporation of the rection mechanism and active site structure – providing deeper insight into the fundamental properties of the catalytic centers that govern catalytic activity. It has the goal to overcoming prevalent approaches that on the one hand are based purely on the thermodynamics of the system (thus ignoring kinetic effects) and on the other hand neglect the electrochemical environment by only considering vacuum simulations of the electrode. The development of various methods that tackle the challenges arising from the complex geometric and electronic structure of the studied system allowed us to study the ratedetermining step of the OER under most conditions, the water addition step, for various 3d transition metal doped active site motifs embedded into a Co3O4 electrode in great detail. This led to the development of a kinetics-based catalyst design strategy that pinpoints the catalytic activity of the active sites to the redox potentials of the involved metal centers. While adapting to recent major developments in the field of modeling electrochemical systems, i.e. grand-canonical simulations that can accurately incorporate electrode-potential and pH effects, this activity study did incorporate kinetic effects, the detailed rection mechanism and various active site structures, but yet was only performed using vacuum simulations and a simple approach to include electrode-potential effects. In order to improve over these shortcomings, we evaluated how the latest theoretical developments can be adapted and extended to provide simulation techniques and methods that allow a highly accurate assessment of the electrocatalytic activity of TMOs for the OER leading to several studies tackling major challenges imposed by the complexity of the system. This included work on how the electrolyte can be modeled with a mixed explicit-implicit treatment in order to provide a sensible representation of the interfacial water environment, several studies analyzing how adsorption energetics depend on the local structure of the surface in an electrochemical environment, and finally the development of a set of methods that allow an accurate, yet highly efficient and a practically DFT-code-independent determination of kinetic barriers at applied electrode potential conditions necessary for an accurate determination of kinetic properties. While these new insights and simulation techniques could not yet be employed to improve the developed kinetics-based description of OER activity of TMOs, they nevertheless represent major steps towards a predictive-quality framework to simulate electrocatalytic activities and provide major insights beyond the studied system.
Publications
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Kinetics-Based Computational Catalyst Design Strategy for the Oxygen Evolution Reaction on Transition-Metal Oxide Surfaces. The Journal of Physical Chemistry C, 123(13), 8287-8303.
Plaisance, Craig P.; Beinlich, Simeon D. & Reuter, Karsten
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Electrosorption at metal surfaces from first principles. npj Computational Materials, 6(1).
Hörmann, Nicolas G.; Marzari, Nicola & Reuter, Karsten
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Static and dynamic water structures at interfaces: A case study with focus on Pt(111). The Journal of Chemical Physics, 155(19).
Dávila, López Alexandra C.; Eggert, Thorben; Reuter, Karsten & Hörmann, Nicolas G.
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Field Effects at Protruding Defect Sites in Electrocatalysis at Metal Electrodes?. ACS Catalysis, 12(10), 6143-6148.
Beinlich, Simeon D.; Hörmann, Nicolas G. & Reuter, Karsten
