Interfacial Effects of NiFe-Based Bifunctional Electrocatalysts for Highly Efficient Overall Water Splitting

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