Work

Copper‐Based Nitrides Outperform Phosphides in Nitrate Electroreduction to Ammonia: The Cooperative Role of the Cu 3 N/CuO Interface

Year: 2025

Type: article

Abstract: Binary compounds consisting of Cu(I) and moderately electronegative elements (N, P) are attractive semiconductors for optoelectronic and electrocatalytic applications. This study investigates the electrochemical reduction of nitrate to ammonia (NO 3 RR) using copper‐based catalysts, specifically Cu 3 N and Cu 3 P. Inhibiting the competitive hydrogen evolution reaction and ensuring active hydrogen (H*) for NH 3 production during NO 3 RR pose significant challenges. Our research demonstrates that while Cu₃P is effective in the initial reduction of nitrate to nitrite, it fails to produce NH₃ at more negative potentials due to competition with the hydrogen evolution reaction (HER). In contrast, Cu₃N exhibits remarkable performance, achieving an ammonia yield rate of 48.8 mmol h −1 mmol −1 cat at −0.9 V RHE , accompanied by considerable Faradaic efficiency and durability. The formation of a Cu 3 N/CuO interface during the catalysis is crucial for its activity, facilitating efficient NO 3 RR through a stepwise reduction mechanism. The study provides insights into the surface modifications and mechanistic aspects of these catalysts during NO 3 RR, offering guidance for strategically developing more efficient catalysts for nitrate reduction to ammonia.

Source: ChemCatChem

DOI: 10.1002/cctc.202500156