Enhanced hydrogen evolution reaction activity of FeNi layered double hydroxide modified with Ruthenium nanoparticles at high current density

FeNi layered double hydroxide (FeNi LDH) shows great potential as electrocatalyst for oxygen evolution reaction (OER) in alkaline media. However, the performance of FeNi LDH in alkaline environments is relatively bad for the hydrogen evolution reaction (HER). In this study, an attractive strategy is presented for significantly improving the HER performance of FeNi LDH by loading Ru. The as-produced Ru-loading FeNi LDH (Ru/ FeNi LDH) reveals excellent HER activity in 1 M KOH (127 mV at 1000 mA cm-2), which is superior to commercial Pt/C electrode and other reported advanced catalysts. Experimental and density functional theory (DFT) calculation results indicate that combining Ru and FeNi LDH can extremely increase the charge transfer rate, active sites, and reduce the kinetic energy barrier, thus enhancing HER performances. The Ru/FeNi LDH || FeNi LDH cell can achieve a high current density at a low voltage under alkaline conditions (1.74 V at 1000 mA cm-2). Moreover, the cell is capable of operating at 500 mA cm-2 for more than 1800 h. The excellent HER activities and stability of Ru/FeNi LDH suggest its potential for practical applications in industrial water splitting.