Synthesis of NiFe-Fc-MOF/LDH/NF with tip effect enhancing electric field for oxygen evolution reactions

Non-noble metal-based electrocatalysts for the oxygen evolution reaction (OER) undergo detachment during the electrocatalytic process, posing a considerable challenge to the large-scale production of “green” hydrogen. Herein, we report a facile strategy for synthesizing NiFe-Fc-MOF/LDH/NF electrocatalysts featuring a rebar-concrete-like structure with enhanced mechanical and catalytic stability, as well as a superhydrophilic/superaerophobic surface structure derived from LDH that enables rapid bubble desorption. In-situ Raman results demonstrate that the NiOOH serves as the main contributor to catalytic active sites. Combined with the structural advantages formed with LDH, the electrode material exhibits excellent OER catalytic performance, achieving an overpotential of only 199 mV at the current density of 10 mA cm⁻² and maintaining stable operation for 200 h without degradation. Finite element simulations confirm that the tip-enhanced local electric field of the needle-like LDH can optimize the charge density and OH⁻ concentration on the electrode surface, thereby accelerating the OER reaction kinetics.