Electronic modulation with Pt-incorporated NiFe layered double hydroxide for ultrastable overall water splitting at 1000 mA cm−2

Achieving large current density is crucial to the practical application of large-scale hydrogen production by water splitting, but it is hindered by sluggish and unstable catalysts. Herein, a Pt-induced NiFe layered double hydroxide (Pt-NiFe LDH) nanosheet is synthesized for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). It affords 10 mA cm –2 at overpotentials of only 198 mV and 36 mV for OER and HER, respectively. Impressively, an alkali-electrolyzer (Pt-NiFe LDH || Pt-NiFe LDH) exhibits a stable cell voltage of 1.887 V to deliver a current density of 1000 mA cm –2 over 3000 h. The introduction of Pt modulates the electronic structure on the surface of NiFe LDH by charging redistribution at the interface and decreasing the Gibbs free energy change (ΔG) for the potential determining step (from *O to *OOH) during OER. This work provides a facile strategy for developing catalysts for large current density water splitting.