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Inorganic nitrogen oxide (NOx) species, such as NO, NO2, NO3−, NO2− generated from the decomposition of organic matters, volcanic eruptions and lightning activated nitrogen, play important roles in the nitrogen cycle system and exploring the origin of life. Meanwhile, excessive emission of NOx gases and residues from industry and transportation causes troubling problems to the environment and human health. How to efficiently handle these wastes is a global problem. In response to the growing demand for sustainability, scientists are actively pursuing sustainable electrochemical technologies powered by renewable energy sources and efficient utilization of hydrogen energy to convert NOx species into high‐value organonitrogen chemicals. In this minireview, recent advances of electrocatalytic systems for NOx species valorization in organonitrogen synthesis are classified and described, such as amino acids, amide, urea, oximes, nitrile etc. that have been widely applied in medicine, life science and agriculture. Additionally, the current challenges including multiple side reactions and complicated paths, viable solutions along with future directions ahead in this field are also proposed. The coupling electrocatalytic systems provide a green mode for fixing nitrogen cycle bacteria and bring enlightenment to human sustainable development. [ABSTRACT FROM AUTHOR]

Pyridine oximes produced from aldehyde or ketone with hydroxylamine (NH2OH) have been widely applied in pharmaceutics, enzymatic and sterilization. However, the important raw material NH2OH exhibits corrosive and unstable properties, leading to substantial energy consumption during storage and transportation. Herein, this work presents a novel method for directly synthesizing highly valuable pyridine oximes using in situ generated NH2OH from electrocatalytic NO reduction with well‐design nanofiber membranes (Al‐NFM) derived from NH2‐MIL‐53(Al). Particularly, 2‐pyridinealdoxime, the precursor of antidote pralidoxime (2‐PAM) for nerve agents suffering from scarcity and high cost, was achieved with a Faraday efficiency up to 49.8 % and a yield of 92.1 %, attributing to the high selectivity of NH2OH production on Al‐NFM, further easily reacted with iodomethane to produce 2‐PAM. This study proposes a creative approach, having wide universality for synthesizing pyridine and other oximes with a range of functional groups, which not only facilitates the conversion of exhaust gas (NO) and waste water (NO2−) into valuable chemicals especially NH2OH production and in situ utilization through electrochemistry, but also holds significant potential for synthesis of neuro detoxifying drugs to humanity security. [ABSTRACT FROM AUTHOR]

The conversion of industrial exhaust gases of nitrogen oxides into high‐value products is significantly meaningful for global environment and human health. And green synthesis of amino acids is vital for biomedical research and sustainable development of mankind. Herein, we demonstrate an innovative approach for converting nitric oxide (NO) to a series of α‐amino acids (over 13 kinds) through electrosynthesis with α‐keto acids over self‐standing carbon fiber membrane with CoFe alloy. The essential leucine exhibits a high yield of 115.4 μmol h−1 corresponding a Faradaic efficiency of 32.4 %, and gram yield of products can be obtained within 24 hours in lab as well as an ultra‐long stability (>240 h) of the membrane catalyst, which could convert NO into NH2OH rapidly attacking α‐keto acid and subsequent hydrogenation to form amino acid. In addition, this method is also suitable for other nitrogen sources including gaseous NO2 or liquidus NO3− and NO2−. Therefore, this work not only presents promising prospects for converting nitrogen oxides from exhaust gas and nitrate‐laden waste water into high‐value products, but also has significant implications for synthetizing amino acids in biomedical and catalytic science. [ABSTRACT FROM AUTHOR]

How to transfer industrial exhaust gases of nitrogen oxides into high‐values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α‐amino acids from nitric oxide (NO) by reacting with α‐keto acids through electrocatalytic process with atomically dispersed Fe supported on N‐doped carbon matrix (AD‐Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mgcat−1 is delivered at −0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X‐ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α‐keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α‐amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO3−). Our findings not only provide a creative method for converting nitrogen oxides into high‐valued products, which is of epoch‐making significance towards artificial synthesis of amino acids, but also benefit in deploying near‐zero‐emission technologies for global environmental and economic development. [ABSTRACT FROM AUTHOR]