Electronic Buffering Mechanism Enhances Stability and Water Oxidation Efficiency of CeO2@NiFe-LDH

Nickel-iron layered double hydroxide shows significant promise as an electrocatalyst in facilitating oxygen evolution reactions. But its development is hindered by low conductivity and insufficient cycling stability. Herein, the synthesis of a hierarchically structured heterostructure catalyst, CeO2@NiFe LDH, is reported through a straightforward two-step process involving hydrothermal treatment. The catalyst realizes a significant breakthrough in OER catalytic performance and stability. At a current density of 100 mA cm-2, the overpotentials amount to 255 mV in 1 M KOH, 263 mV in simulated seawater with alkaline conditions, and 346 mV in actual alkaline seawater. After 200 hours of continuous operation under high current density in simulated alkaline seawater, the morphology with no significant alterations observed, highlighting its high stability in complex seawater environments. Introducing CeO2 optimizes the binding energy of the OH intermediate, which facilitates the formation and dissociation of the OOH intermediate. In situ Raman analysis demonstrates the positive impact of CeO2 on the generation of active species. This research emphasizes the efficacy of CeO2 in improving the performance and durability of NiFe LDH for oxygen evolution reactions.