Ultrahigh-current-density Fe-doped NiCr layered double hydroxide as a robust bifunctional electrocatalyst for overall...

Layered double hydroxides (LDHs) have been extensively investigated due to their two-dimensional lamellar structure and tunable interlayer anions. NiCrLDH has attracted increasing attention owing to the unique octahedral geometry of Cr, yet its intrinsic catalytic performance remains moderate among various materials. Herein, Fe was incorporated into the NiCrLDH system via a one-step hydrothermal method to modulate the electronic structure of Ni sites and enhance catalytic activity. For the oxygen evolution reaction (OER), the material required only 282.3 mV overpotential to achieve 100 mA cm^-2 in 1 M KOH electrolyte, with current densities exceeding 1 A cm^-2 at 368.3 mV overpotential. It also demonstrated excellent performance as a hydrogen evolution reaction (HER) catalyst. Furthermore, the material exhibited high stability in alkaline seawater, maintaining a catalytic activity of 1.983 V at 10 mA cm^-2 after 50 h of overall water splitting cycling.