Nitrogen contained rhodium nanosheet catalysts for efficient hydrazine oxidation reaction.

The hydrazine oxidation reaction (HzOR) has been considered as a more energy-efficient alternative to the oxygen evolution reaction in water electrolysis. To design efficient electrocatalysts for HzOR, precise engineering of materials is required to increase active sites and build electronic structures. Herein, nitrogen contained face-centered cubic rhodium (N-fcc-Rh) nanosheets are prepared by directly annealing metastable trigonal rhodium oxide precursor in the ammonia atmosphere. Benefiting from the abundant active sites and unique electronic structure, the optimal N-fcc-Rh-300 electrocatalyst achieves an ultra-low working potential of − 81 mV (vs. RHE) at 10 mA cm−2 in 1.0 M KOH/0.5 M N 2 H 4. Density functional theory calculations suggest the N element in the N-fcc-Rh electrocatalyst enables to the reduction of the formation energy of the potential-determining step from *NH 2 NH 2 to *NHNH 2 for the HzOR process. This work reveals a new strategy to prepare advanced metal electrocatalysts for various electrochemical applications. [Display omitted] • Nitrogen contained face-centered cubic rhodium nanosheets. • Excellent HzOR activity with working potential of − 81 mV (vs. RHE) at 10 mA cm−2. • N elements into Rh leads to a shift of the d-band center away from the Fermi level. [ABSTRACT FROM AUTHOR]