Metal Hydroxide-Organic Framework Mediated Structural Reengineering Enables Efficient NiFe Interaction for Robust Water Oxidation.

NiFe layered double hydroxide (NiFe LDH) derived oxyhydroxides are promising electrocatalysts for the alkaline oxygen evolution reaction (OER). However, NiFe LDH with a stable metal-oxygen-metal (M-O-M) structure suffers from inadequate NiFe interaction, leading to undesirable activity and stability. Herein, we develop a NiFe hydroxide-organic framework (NiFe HOF) via modification of NiFe LDH with an organic linker to break the structural constraint of M-O-M and thus boost the OER. NiFe HOF with reconfigurable metal sites facilitates structural reengineering under the OER condition to form abundant NiFe interaction and prolonged M-O bonds, stimulating lattice oxygen mechanism. Therefore, NiFe HOF shows a distinctly decreased overpotential at 50 mA cm ^-2 , which is 68 mV lower than that of NiFe LDH. The anion exchange membrane electrolyzer using NiFe HOF as anode electrode displays ultralong stability exceeding 1050 h at 1 A cm ^-2 with a low attenuation of 0.16 mV h ^-1 .