Inert Mg Incorporation to Break the Activity/Stability Relationship in High-Entropy Layered Hydroxides for the Electrocatalytic Oxygen Evolution Reaction

Ni-based layered double hydroxides (LDHs) have been demonstrated as the most active catalyst for the oxygen evolution reaction in alkaline media but suffer from poor stability. Herein, we report the rational breaking of the activity/stability trade-off by a strategy of inert Mg-involved high-entropy coordination. The as-developed high-entropy FeCoNiMg-LDH nanosheets exhibit not only high catalytic activity (302 mV at 100 mA cm–2) but also an unprecedented stability with almost no performance decline at a large current density of 300 mA cm–2. The combined structural investigations and theoretical calculations reveal that the synergistic electronic coupling provides active Ni in desired electronic states, leading to an optimized adsorption energy of intermediates, while the construction of high configuration entropy as well as the formation of the Mg–O interfacial bond can effectively mitigate phase segregation and transformation and thus improve the stability. The current insights into unveiling the composition–activity–stability of high-entropy coordination may provide valuable guidance for the design of catalysts for various electrochemical reactions.