(175e) Embracing the Complexity of Catalytic Structures: Engineering Nonstoichiometric Mixed Metal Oxides for Electrocatalysis

Dwindling fuel resources and high levels of CO₂ emissions have accelerated the need for renewable energy resources and more efficient energy conversion and storage systems. We focus on engineering complex, non-stoichiometric mixed metal oxides as a potential avenue for addressing limitations with the current state-of-the-art metal based electrocatalysts. The compositional versatility of non-stoichiometric metal oxides belonging to the perovskite family, of the general form A_n+1B_nO_3n+1 (n = 1, 2, 3... ; A = rare earth/alkaline earth metal; B = transition metal), presents numerous opportunities to tune the catalytic performance of these oxides for targeted reactions. However, identification of nonstoichiometric metal oxides for these reactions is often limited by their complexity and lack of effective descriptors of their activity and stability. We have combined theory, advanced characterization, controlled synthesis and electrochemical studies to shed light on the factors that govern electrochemical reduction and evolution of oxygen along with electrochemical reduction of CO₂ to CO on these oxides and have identified ways to tune their activity and stability.^1-5 These studies have paved the way for engineering active and stable cationic centers in nonstoichiometric mixed metal oxide electrocatalysts for targeted reaction chemistries.

References

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