Enhance water electrolysis performance of Ru nanoparticles-modified Ni/NiO three-phase heterojunctions under alkaline conditions

Reasonably designing and optimizing the homogenous surfaces of catalysts with moderate noble metal loadings to enhance their electrolysis of water performance in alkaline environments has always been a challenge. In this work, we proposed a heterostructure induction technique employing Ru nanoparticles, Ni, and NiO to accurately produce a highly distributed three-phase heterostructure Ru@Ni/NiO, which exhibits excellent catalytic performance for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and overall water splitting reaction under alkaline conditions. The OER overpotentials in 1 M KOH were 250 mV, 320 mA, and 350 mV at 10 mA cm −2 , 50 mA cm −2 , and 100 mA cm −2 current densities, respectively, outperforming RuO 2 . The HER overpotentials were 52 mV, 107 mV, and 142 mV, respectively, superior to Pt/C. In the overall water splitting reaction, the Ru@Ni/NiO system requires only 1.63 V, 1.94 V and 2.08 V to achieve current densities of 10 mA cm −2 , 50 mA cm −2 and 100 mA cm −2 , respectively. Meanwhile, the catalyst exhibited excellent stability at high current density. This study provides a design strategy for the precise construction of interfacial engineering and demonstrates significant potential for large-scale hydrogen production via electrochemical water splitting.