Controllable synthesis for highly dispersed ruthenium clusters confined in nitrogen doped carbon for efficient hydrogen evolution

Modulating the size and dispersion of metal particles is highly desirable in nanocatalysis. Herein highly dispersed ruthenium clusters confined in nitrogen-doped carbon (RuNC) were synthesized by a one-pot pyrolysis of Ru(phen) 3 organometallic compounds and glucose. The size of the Ru clusters was finely controlled at a cluster level (1.7 nm) to expose more catalytic active sites. The interaction between the Ru clusters and N species not only facilitated the uniform dispersion, but also prevented the aggregation of Ru clusters. This cluster-level RuNC manifested extraordinary catalytic performance towards the hydrogen evolution reaction (HER) and was comparable to or even better than a commercial Pt/C catalyst in basic and acidic media, respectively. Moreover, based on density functional theory (DFT) calculations, it was demonstrated that the N dopants in the carbon framework efficiently tailored the charge density distribution of the Ru centres and promoted the adsorption of H* on the catalyst, thus contributing to the high catalytic activity.