Construction of a ruthenium-doped CoFe-layered double hydroxide as a bifunctional electrocatalyst for overall water splitting.

In this study, ruthenium-doped CoFe-based layered double hydroxides on Ni foam (CoFe-ZLDH/Ru@NF) were fabricated an etching-precipitation strategy. The resultant CoFe-ZLDH/Ru@NF exhibited excellent activity, showing low overpotentials of 219.8 mV and 60.9 mV to reach the current density of 10 mA cm for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. As a bifunctional electrocatalyst, it was assembled in an anion exchange membrane water electrolyser (AEMWE) unit, performing as an anode and cathode simultaneously, which only required a cell voltage of 2.33 V to accomplish the industrial level current density of 1 A cm and operated steadily for over 12 h, making it promising for utilization in hydrogen production.