Interfacial Engineering Enhances the Electroactivity of Frame-Like Concave RhCu Bimetallic Nanocubes for Nitrate Reduction

Ammonia is a crucial chemical in agriculture, industry, and emerging energy industries, so high-efficient, energy-saving, sustainable, and environmentally-friendly NH3 synthesis strategies are highly desired. Here polyallylamine (PA) functionalized frame-like concave RhCu bimetallic nanocubes (PA-RhCu cNCs) are reported with an electrochemically active surface area of 72.8 m(2) g(-1) as a robust electrocatalyst for the 8e reduction of nitrate (NO3-) to NH3. PA-RhCu cNCs show a remarkable NH3 production yield of 2.40 mg h(-1) mg(cat)(-1) and a high faradaic efficiency of 93.7% at +0.05 V potential. Density functional theory calculations and experimental results indicate that Cu and PA (adsorbed amino) coregulate the Rh d-band center, which slightly weakens the adsorption energy of reaction-related species on Rh. In addition, the electrochemical interface mass transfer accelerated by the surface PA further determines the notable performance of PA-RhCu cNCs for electroreduction of NO3- to NH3. These findings may open an avenue to construct other advanced catalysts based on organic molecule-mediated interfacial engineering in various catalysis/electrocatalysis fields.