(544gs) Trends in Adsorption of Electro-Catalytic Water Splitting Intermediates on Hetero-Structures of Perovskite Oxides

Electrochemical and photo-electrochemical water splitting are promising routes in realizing a sustainable energy future based on a hydrogen economy. However, suitable catalysts are needed to drive the constituent reactions involved in water splitting; the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), due to their sluggish kinetics. Certain perovskite oxides have been shown to be potential candidates that effectively catalyze this reaction^1-3, but are more often than not composed of transition metals that are not earth abundant, and frequently have issues with their long-term stability. To potentially circumvent this issue, we use the strategy of near surface alloying (NSA) to computationally design hetero-structures of perovskite oxides based on a stable host perovskite with a near surface doped B-site metal. Using this strategy, we studied the possible different B-site dopants among the transition metals, and their effects on the binding energies of the different electro-catalytic intermediates in the water splitting sub-reactions. We also analyzed the correlations between the electronic structure and activity induced by the different dopants. Based on this scheme, we identify candidate perovskite oxides that can be used to catalyze both the OER and the HER.

Keywords: water splitting, OER, HER, perovskite, hetero-structures

Reference:

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