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Mitigating nitrogen oxide (NO x ) emissions is critical to tackle global warming and improve air quality. Conventional NO x abatement technologies for emission control suffer from a low efficiency at near ambient temperatures. Herein, we show an electrochemical pathway to reduce gaseous NO x that can be conducted at high reaction rates (400 mA cm–2) under ambient conditions. Various transition metals are evaluated for electrochemical reduction of NO and N2O to reveal the role of electrocatalyst in determining the product selectivity. Specifically, Cu is highly selective toward NH3 formation with >80% Faradaic efficiency in NO electroreduction. Furthermore, the partial pressure study of NO electroreduction revealed that a high NO coverage facilitates the N–N coupling reaction. In acidic electrolytes, the formation of NH3 is greatly favored, whereas the N2 production is suppressed. Additional mechanistic studies were conducted by using flow electrochemical mass spectrometry to gain further insights into reaction pathways. This work provides a promising avenue toward abating gaseous NO x emissions at ambient conditions by using renewable electricity.

Nanostructured Cu catalysts have increased the selectivities and geometric activities for high value C-C coupled (C2) products (ethylene, acetate, and ethanol) in the electrochemical CO(2) reduction reaction (CO(2)RR). The selectivity...

The electroreduction of carbon dioxide offers a promising avenue to produce valuable fuels and chemicals using greenhouse gas carbon dioxide as the carbon feedstock. Because industrial carbon dioxide point sources often contain numerous contaminants, such as nitrogen oxides, understanding the potential impact of contaminants on carbon dioxide electrolysis is crucial for practical applications. Herein, we investigate the impact of various nitrogen oxides, including nitric oxide, nitrogen dioxide, and nitrous oxide, on carbon dioxide electroreduction on three model electrocatalysts (i.e., copper, silver, and tin). We demonstrate that the presence of nitrogen oxides (up to 0.83%) in the carbon dioxide feed leads to a considerable Faradaic efficiency loss in carbon dioxide electroreduction, which is caused by the preferential electroreduction of nitrogen oxides over carbon dioxide. The primary products of nitrogen oxides electroreduction include nitrous oxide, nitrogen, hydroxylamine, and ammonia. Despite the loss in Faradaic efficiency, the electrocatalysts exhibit similar carbon dioxide reduction performances once a pure carbon dioxide feed is restored, indicating a negligible long-term impact of nitrogen oxides on the catalytic properties of the model catalysts.

Electrifying chemical manufacturing using renewable energy is an attractive approach to reduce the dependence on fossil energy sources in chemical industries. Primary amines are important organic building blocks; however, the synthesis is often hindered by the poor selectivity because of the formation of secondary and tertiary amine byproducts. Herein, we report an electrocatalytic route to produce ethylamine selectively through an electroreduction of acetonitrile at ambient temperature and pressure. Among all the electrocatalysts, Cu nanoparticles exhibit the highest ethylamine Faradaic efficiency (~96%) at −0.29 V versus reversible hydrogen electrode. Under optimal conditions, we achieve an ethylamine partial current density of 846 mA cm−2. A 20-hour stable performance is demonstrated on Cu at 100 mA cm−2 with an 86% ethylamine Faradaic efficiency. Moreover, the reaction mechanism is investigated by computational study, which suggests the high ethylamine selectivity on Cu is due to the moderate binding affinity for the reaction intermediates.