Structural tuning and reconstruction of CeO2-coupled nickel selenides for robust water oxidation

Heterogeneous catalysts have attracted wide attention due to their remarkable oxygen evolution reaction (OER) capabilities. Herein, a one-step strategy involving the coupling of NixSey with CeO2 is proposed to concurrently construct heterogeneous interfaces, adjust phase structure, and regulate electronic configuration, thereby enhancing OER performance. Thanks to the role of CeO2 coupling in reducing the activation-energy and accelerating the reaction kinetics, the heterogeneous NixSey/CeO2 catalyst exhibits a low overpotential of 218 mV at 10 mA/cm2 and long-term stability (>400 h) in 1.0 mol/L KOH for OER. Moreover, the post-OER characterization reveals that the NixSey matrix is reconstructed into NiOOH, while the incorporated CeO2 nanocrystals self-assemble into larger polycrystalline particles. Theoretical analysis further demonstrates that the optimized electronic states at NiOOH/CeO2 interfaces can modulate intermediate chemisorption toward favorable OER kinetics. This study offers fresh perspectives on the synthesis and structure-activity relationship of CeO2-coupled electrocatalysts. A one-step strategy involving the coupling of NixSey catalysts with CeO2 is proposed to concurrently construct heterogeneous interfaces, adjust phase structure, and regulate electronic configuration, thereby enhancing OER performance. [Display omitted]