Engineering single atomic ruthenium on defective nickel vanadium layered double hydroxide for highly efficient hydrogen evolution

Fabricating single-atom catalysts(SACs)with high catalytic activity as well as great stability is a big challenge.Herein,we propose a precise synthesis strategy to stabilize single atomic ruthenium through regulating vanadium defects of nickel vanadium layered double hydroxides(NiV-LDH)ultrathin nanoribbons support.Correspondingly,the isolated atomically Ru doped NiV-LDH ultrathin nanoribbons(NiVRu-R)were successfully fabricated with a super-high Ru load of 12.8 wt.%.X-ray absorption spectrum(XAS)characterization further confirmed atomic dispersion of Ru.As catalysts for electrocatalytic hydrogen evolution reaction(HER)in alkaline media,the NiVRu-R demonstrated superior catalytic properties to the commercial Pt/C.Moreover,it maintained exceptional stability even after 5,000 cyclic voltammetry cycles.In-situ XAS and density functional theory(DFT)calculations prove that the Ru atomic sites are stabilized on supports through forming the Ru-O-V structure,which also help promote the catalytic properties through reducing the energy barrier on atomic Ru catalytic sites.