Interfacial\nEffects of NiFe-Based Bifunctional Electrocatalysts\nfor Highly Efficient Overall Water Splitting

The reasonable design of highly efficient NiFe-based\nbifunctional\nelectrocatalysts is imperative for water splitting and alleviation\nof the energy crisis. Herein, the NiFe-based bifunctional electrocatalysts\nare designed and grown in situ on Ni foam by a simple hydrothermal\nmethod. The interfacial effect among NiFe-LDH, Fe<sub>5</sub>O<sub>7</sub>(OH), and NiFe<sub>2</sub>O<sub>4</sub> exposes more catalytic\nactive sites, modulated electronic structure, and optimization of\nthe electrocatalytic performances. The overpotentials of NiFe-LDH/Fe<sub>5</sub>O<sub>7</sub>(OH)/NiFe<sub>2</sub>O<sub>4</sub>/NF-15h (NFN/NF-15h)\nfor the hydrogen evolution reaction (HER) and oxygen evolution reaction\n(OER) are 78 and 208 mV at 10 mA cm<sup>–2</sup>, respectively.\nOverall water splitting can drive 10 mA cm<sup>–2</sup> with\na cell voltage of only 1.538 V. This work contributes a feasible idea\nfor the design and synthesis of NiFe-based bifunctional electrocatalysts\nwith outstanding water splitting performance.