High-performance overall water electrolysis enabled by a one-step fabricated bifunctional Pt/NiFe LDH catalyst on iron nickel foam

Abstract

The development of bifunctional electrocatalysts with high efficiency for overall water splitting is still a challenging task. In this work, we introduce a novel one-step synthesis method for Pt/NiFe layered double hydroxide (LDH) on an iron-nickel foam (INF) substrate under mild conditions. This method eliminates the need for additional Ni or Fe ions and facilitates in-situ etching and growth processes under mild conditions, resulting in a higher active surface area, well-dispersed low-loading Pt nanoparticles, and a self-supported electrode without binders. These features collectively enhance electron transfer and catalytic activity for both HER and OER. The Pt/NiFe LDH/INF exhibits remarkable water splitting performance, requiring a cell voltage of only 1.44 V at10 mA cm⁻² when used as both anode and cathode. Additionally, it remains stable at 20 mA cm⁻² for at least 16 h. The exceptional water splitting activity of Pt/NiFe LDH/INF in alkaline solution can be attributed to the synergistic effects of Pt and NiFe LDH, which improve the hydrogen evolution reaction and oxygen evolution reaction efficiencies. The results provide valuable insights into designing bifunctional electrocatalysts with low Pt loading for optimal water splitting performance at low operating cost.