Surfactant-free atomically ultrathin rhodium nanosheet nanoassemblies for efficient nitrogen electroreduction

Abstract

In this work, surfactant-free atomically ultrathin Rh nanosheet nanoassemblies (Rh NNs) are synthesized and used for the first time as an effective electrocatalyst in the nitrogen reduction reaction (NRR) at ambient temperature and pressure. The inorganic polymer RhCl₃–K₃Co(CN)₆ cyanogel plays an important role in the generation of ultrathin Rh nanosheets with a clean surface. Due to their unique ultrathin two-dimensional nanosheet structure (ca. 1 nm) with a high specific surface area and modified electronic structure, the surfactant-free Rh NNs demonstrate an excellent catalytic activity for the NRR with a high production yield (NH₃: 23.88 μg h⁻¹ mg_cat⁻¹) and favorable selectivity (no N₂H₄ generation) at low potential (−0.2 V vs. RHE), outperforming most of the current electrocatalysts reported for the NRR. Except the contribution to the efficient NRR electrocatalysis, this synthesis strategy would provide some new insights into the preparation of ultrathin precious metal nanosheets for energy related applications.