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DOE OSTI · 3008122

Enhanced Activity in Layered Metal-Oxide-Based Oxygen Evolution Catalysts by Layer-by-Layer Modulation of Metal-Ion Identity

Ding, Ran [Temple University, Philadelphia, PA (United States); North Carolina State University, Raleigh, NC (United States)]·Maldonado-Lopez, Daniel [Michigan State University, East Lansing, MI (United States)]·Henebry, Jacob E. [Temple University, Philadelphia, PA (United States)]·Mendoza-Cortes, Jose [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000151841406)·Zdilla, Michael J. [Temple University, Philadelphia, PA (United States)] (ORCID:0000000302122557)
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Abstract

Few-layered potassium nickel and cobalt oxides show drastic differences in catalytic activity based on metal ion preorganization. Uniform compositions [(CoO 2 /K) 6 or (NiO 2 /K) 6 ] show limited activity, while homogeneously mixed-metal cobalt/nickel oxides [(Co n Ni (1–n) O 2 /K) 6 ] display moderate improvement. However, a layer-by-layer arrangement of alternating cobalt and nickel oxide sheets [e.g., (CoO 2 /K/NiO 2 /K)] provides superior catalytic performance, reducing the oxygen evolution overpotential by ∼200–400 mV. Density functional theory simulations provide an illustration of the electronic properties (density of states and localization of orbitals) that promote catalysis in the layer-segregated materials over those of homogeneous composition. This study reveals that atomic preorganization of metal ions within layered catalysts plays a more crucial role than the overall metal composition in enhancing catalytic efficiency for oxygen evolution.

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catalystselectrocatalysisheterogeneous catalysislayered materialslayersmaterialsoxideswater oxidationwater splitting

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Ding, Ran [Temple University, Philadelphia, PA (United States); North Carolina State University, Raleigh, NC (United States)], Maldonado-Lopez, Daniel [Michigan State University, East Lansing, MI (United States)], Henebry, Jacob E. [Temple University, Philadelphia, PA (United States)], Mendoza-Cortes, Jose [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000151841406), Zdilla, Michael J. [Temple University, Philadelphia, PA (United States)] (ORCID:0000000302122557). 2025-11-24. Enhanced Activity in Layered Metal-Oxide-Based Oxygen Evolution Catalysts by Layer-by-Layer Modulation of Metal-Ion Identity. https://doi.org/10.1021/acscatal.5c02788

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