Interface Engineering with Ultralow Ruthenium Loading for Efficient Water Splitting

Abstract

Developing high-performance and cost-effective bifunctional electrocatalysts for water splitting is the key to large-scale hydrogen production. How to achieve higher performance with lower amount of noble metal is still a major challenge. Herein, by a facile wet-chemistry strategy, we report the ultra-low amount of ruthenium (Ru) loading on porous nickel foam (NF) as highly efficient bifunctional electrocatalysts for water splitting. Theoretical simulations reveal that the coupling effect of Ru and Ni can significantly reduce the d-band center of the composite. The Ru-modified NF exhibits a very high level of HER activity with only 0.3 wt% amount of Ru, far surpassing commercial Pt/C. It only requires an extremely low overpotential (η10) of 10 mV to achieve a current density of 10 mA cm-2 in alkaline solution and a quite low Tafel slope of 34 mV dec-1. This catalyst also shows remarkable performance for overall water splitting with a low voltage of 1.56 V at 10 mA cm-2. These findings indicate the potential of this material in water-alkali electrolyzers, providing a new approach for fabrication of low-cost advanced electrocatalysts.