【Frontiers in HaiChuan Chemical Technology】Dalian Institute of Chemical Physics achieves efficient ammonia synthesis from electrocatalytically produced high-pressure nitric oxide

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I have achieved efficient ammonia synthesis via electrocatalytic high-pressure nitric oxide reduction. Recently, the research team led by Researcher Deng Dehui, Associate Researcher Cui Xiaoju, and Researcher Yu Liang from the Energy and Environmental Small Molecule Catalysis Research Center (Group 509) at the **Key Laboratory of Catalytic Fundamentals of the Dalian Institute of Chemical Physics made new progress in the study of electrocatalytic ammonia synthesis using nitric oxide. The team innovatively developed a high-pressure-electrocatalytic system and created an integrated Cu nanowire array catalyst with a unique three-dimensional multi-level porous structure, enabling the efficient and long-lasting electrocatalytic synthesis of ammonia from nitric oxide at amperage-level current densities. This work provides new ideas for the resource utilization of nitrogen monoxide pollutants in industrial exhaust gases and for green, sustainable ammonia electrosynthesis processes. Globally, more than 69 million tons of nitrogen oxides (NOx) are emitted each year, with the industrial synthesis processes of adipic acid and nitric acid being the main sources of high concentrations of nitric oxide (NO). Meanwhile, ammonia, as an essential basic chemical in modern society, plays a key role in the manufacture of fertilizers and the production of nitrogen-containing chemicals. To meet the requirements for NO pollution control and the sustainable development of ammonia synthesis, the electrochemical reduction of NO to produce ammonia offers a promising technical approach. However, this technology still faces issues such as the low solubility of NO in aqueous solutions, which severely limits its mass transfer efficiency, as well as the hydrogen evolution side reaction during electrochemical reduction, which restricts the Faradaic efficiency of ammonia synthesis. The Dundee team has made a series of advances in electrochemical nitrogen cycling earlier on (Nat. Synth., 2024 ； Natl. Sci. Rev., 2022 ； Chem Catal., 2022 ； Angew. Chem. Int. Ed., 2020). In addition, the team utilized high-pressure electrochemical reactors to achieve efficient electrocatalytic conversion of small energy molecules such as methane (J. Am. Chem. Soc., 2024) ； J. Energy Chem., 2023). On this basis, in this work the team designed and synthesized an integrated Cu nanowire array electrode with a three-dimensional multi-level porous structure; combined with a self-developed high-pressure electrochemical reaction device, this enabled the efficient electrocatalytic synthesis of ammonia from nitric oxide. In this system, the Faradaic efficiency remains at 96.1% when the current density for ammonia production reaches 1007 mA cm-2; the ammonia generation rate is 10.5 mmol h-1 cm-2, which is more than 10 times higher than that of commercial foam copper under normal pressure. It can also operate stably for over 100 hours at a high current density of 1000 mA cm-2, demonstrating excellent potential for industrial application. Experimental characterization and theoretical calculation results show that the multi-level porous structure of the Cu nanowire array electrode maximally exposes active sites and enhances internal mass transfer efficiency ； On the other hand, increasing the NO partial pressure raises the solubility of NO and promotes its diffusion and mass transfer; it also increases the coverage of NO on the Cu surface, thereby moderately weakening the interaction between Cu and the adsorbed NO*. This facilitates the hydrogenation of NO to ammonia while effectively suppressing the competitive hydrogen evolution reaction. This work not only provides a new technical strategy for the electrocatalytic synthesis of ammonia from NO at industrial current densities, but also offers new insights for the efficient electrocatalytic conversion of other small gas molecules. The relevant research findings were published recently in Nature Communications under the title “Electrosynthesis of NH3 from NO with ampere-level current density in a pressurized electrolyzer”. The above work was supported by projects such as the **Key Research and Development Program**, the National Natural Science Foundation of China, the Chinese Academy of Sciences’ program for supporting young teams in basic research, and the Chinese Academy of Sciences’ Category B pilot project titled “Principles and Methods for the Precise Construction of Functional Nanosystems”.