Ultrafine Ir nanoparticles decorated on FeP/FeOOH with abundant interfaces via a facile corrosive approach for alkaline water-splitting

Abstract

In order to generate clean hydrogen fuel, it is necessary to exploit bifunctional catalysts with high activity and excellent stability for overall water-splitting. Herein, we develop ultrafine Ir nanoparticles coupled with FeP/FeOOH with abundant interfaces on iron foam (FF) via facile corrosive strategies. The ingeniously designed catalyst structure not only exposes abundant active centers, but also enhances the electron transport efficiently. Thus, the FF–NaCl–Ir–P catalyst exhibits outstanding catalytic activities for the OER (169 mV at 10 mA cm⁻²) and HER (69 mV at 10 mA cm⁻²) in 1 M KOH, which was better than most of the previously reported catalysts. For water-splitting, it only needs 1.47 V to reach 10 mA cm⁻², and its performance hardly deteriorates after 50 hours test at a large-current density of 1000 mA cm⁻². The overall water-splitting can also be motivated by simple sustainable energy, such as solar, wind and thermal energies.