Single Co-Atoms as Electrocatalysts for Efficient Hydrazine Oxidation Reaction

Single-atom catalysts (SACs) have aroused great attention due to their high atom efficiency and unprecedented catalytic properties. A remaining challenge is to anchor the single atoms individually on support materials via strong interactions. Herein, single atom Co sites have been developed on functionalized graphene by taking advantage of the strong interaction between Co2+ ions and the nitrile group of cyanographene. The potential of the material, which is named G(CN)-Co, as a SAC is demonstrated using the electrocatalytic hydrazine oxidation reaction (HzOR). The material exhibits excellent catalytic activity for HzOR, driving the reaction with low overpotential and high current density while remaining stable during long reaction times. Thus, this material can be a promising alternative to conventional noble metal-based catalysts that are currently widely used in HzOR-based fuel cells. Density functional theory calculations of the reaction mechanism over the material reveal that the Co(II) sites on G(CN)-Co can efficiently interact with hydrazine molecules and promote the N-H bond-dissociation steps involved in the HzOR.

Automated summary

A single-atom catalyst material named G(CN)-Co has been developed on functionalized graphene, demonstrating excellent catalytic activity for electrocatalytic hydrazine oxidation reaction (HzOR) with low overpotential and high current density, while remaining stable over long reaction times. This material shows promising potential as an alternative to conventional noble metal-based catalysts in HzOR-based fuel cells.