High-stability magnesium-doped nickel iron-layered double hydroxide induced by lattice-interface-electron: Enhanced...

To address the insufficient stability of nickel iron-layered double hydroxide (NiFe-LDH) during the oxygen evolution reaction (OER) at high current densities-caused by structural fatigue, element dissolution, and bubble retention-this study proposes a synergistic magnesium (Mg) doping strategy. X-ray diffraction (XRD) and Raman spectroscopy confirm that Mg²⁺ incorporation into the NiFe-LDH/NF (Nickel foam, NF) layers induces lattice distortion, generating a localized internal stress field that suppresses interlayer slipping and mitigates Fe dissolution. Scanning electron microscopy (SEM) and contact angle tests show that Mg doping triggers self-assembly into an aerophobic three-dimensional nanoflower architecture, facilitating bubble detachment and reducing physical damage. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) analyses reveal that doping promotes electron transfer from Ni to Fe, lowering the work function (W_f) and narrowing the band gap (E_g), thereby alleviating chemical bond dissociation and phase-transformation damage. Together, these three distinct mechanisms enable NiFeMg-LDH/NF to sustain stable operation for over 1100 h at 1000 mA cm^-2 with a 0.9% potential increase, underscoring its promise as an industrial-grade OER catalyst.