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

Abstract Ammonia is a crucial chemical in agriculture, industry, and emerging energy industries, so high‐efficient, energy‐saving, sustainable, and environmentally‐friendly NH 3 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 (NO 3 − ) to NH 3 . PA‐RhCu cNCs show a remarkable NH 3 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 NO 3 − to NH 3 . These findings may open an avenue to construct other advanced catalysts based on organic molecule‐mediated interfacial engineering in various catalysis/electrocatalysis fields.