Simple construction of NiCo-LDH@FeOOH nanoflower heterostructure by chemical etching strategy for efficient oxygen evolution reaction

The large overpotential and slow kinetics of the oxygen evolution reaction (OER) on an anode seriously reduces the water splitting efficiency. Herein, the FeOOH decorated NiCo-layered double hydroxides (NiCo-LDH@FeOOH) nanoflower heterostructure electrocatalyst is synthesized using a simple one-step ZIF-67 derivation and chemical etching strategy. Owing to the unique 3D heterogeneous nanoflowers structure formed by etching, the strong interface interaction regulates the electronic structure, and combined with the synergistic effect between the three metals, the electrochemical activity of the catalyst is significantly increased. NiCo-LDH@FeOOH exhibits superior OER activity with a low overpotential of 255 mV at a current density of 50 mA cm-2 under alkaline conditions and provides long-term durability (73 h). Moreover, ex-periments and density functional theory calculations reveal that the Co-site synergistically promote the OER activity of the Fe site. This study sheds new light on constructing LDH-based heterogeneous composite electrocatalysts.& COPY; 2023 Elsevier B.V. All rights reserved.