Iron-based layered double hydroxide packed with metal–organic frameworks for enhanced overall water-splitting electrocatalysis

Designing hybrid materials with numerous catalytic active sites, high specific surface area, and interfacial interactions is an effective strategy to improve electrocatalytic performance. In this work, iron-based metal organic frameworks (Fe-MOFs)@(Co, Ni)Fe-layered double hydroxide (LDH) is successfully constructed using the similar “MOF growing on LDH” strategy for oxygen evolution reaction and hydrogen evolution reaction in the alkaline electrolyte. The synthesized hybrid materials in this particular way show excellent electrochemical overall water-splitting performance with the cell voltage of 1.62 V at 10 mA·cm⁻² in the alkaline environment due to the optimized adsorption/desorption properties of metal ions on oxygen-containing species and interfacial effects of hybrid materials. Fe-MOFs@(Co, Ni)Fe-LDH also exhibits excellent hydrogen and oxygen production efficiency of 370 and 175 μL·min⁻¹, respectively. This work draws on an effective approach to the fabrication of MOF@LDH structures and provides new insights into overall water-splitting in alkaline conditions.