Promising Ce single-atom-dispersed nitrogen-doped graphene catalysts for the hydrogen evolution reaction

Single-atom (SA) anchored nitrogen-doped graphene (NGr) exhibits potential for efficient hydrogen production because of the advantages of maximum atomic utilization and surface-active energy. However, finding a suitable method for fabricating SA-containing catalysts with the desired metal loading without cluster formation is challenging. Here, well-dispersed Ce SAs on porous NGr catalysts were fabricated via a pyrolysis approach. 1Ce/NGr (1.0 wt% Ce) exhibited potential hydrogen evolution reaction (HER) performance in an alkaline medium: low onset overpotential and high stability, which was comparable to Pt/C (10.0 wt% Pt). The promising performance was attributed to the modification of the coordination environment and electronic structure between Ce SAs and the NGr host, which in turn serve as active sites for facilitating the adsorption and dissociation of water and liberating hydrogen molecules. This work offers new possibilities for designing rare-earth SA-based catalysts for water electrolysis. Ce SAs on porous NGr (1Ce/NGr) show potential for HER with low onset overpotential and high stability. The modified environment of Ce SAs and NGr active sites facilitates water adsorption and dissociation, liberating hydrogen.