▎ 摘　　要

Production of clean hydrogen energy from water splitting is vital for the future fuel industry, and nanocompos-ites have emerged as effective catalysts for the hydrogen evolution reaction (HER). In this study, Ru-CoO@SNG nanocomposites are prepared by controlled pyrolysis where Ru-CoO heterostructured nanoparticles are sup-ported on nitrogen and sulfur codoped graphene oxide nanosheets. With a large surface area, the obtained com-posites exhibit a remarkable electrocatalytic activity toward HER in 1.0 M KOH with an overpotential of only -90 mV to reach the current density of 10 mA cm-2, in comparison to -60 mV for commercial Pt/C bench-mark, along with high stability. Mechanistically, codoping of sulfur and nitrogen facilitates the dispersion of the nanoparticles, and the formation of Ru-CoO heterostructures increases the active site density, reduces the electron-transfer kinetics and boosts the catalytic performance. Results from this study highlight the unique potential of structural engineering in enhancing the electrocatalytic performance of heterostructured nanocomposites.