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Electrocatalytic conversion of waste nitrogen oxide (NOx) into value-added nitrogenous chemicals, especially amino acid, is an emerging strategy to alleviate NOx pollution. However, this process suffers from the coexistence of multiple competitive reactions leading to complex product distribution and low efficiency, and thus the rational design and modulation of efficient catalysts remains a formidable challenge. Herein, well-designed Co nanoparticles encapsulated in hollow carbon nanofiber (Co-HCNF) were constructed to promote the amino acid electrosynthesis via dealing waste NOx coupling with biomass-derived keto acids. Ascribed to the rapid reactant diffusion, electron transport and efficient contact with abundant accessible Co catalytic sites stemmed from the unique hollow nanotubular structure, Co-HCNF manifested impressive glycine synthesis performance in one-pot adopting NO as the nitrogen source with Faradaic efficiency (FE) of 41.7% and a corresponding yield rate of 222.3 µmol h−1 as well as 120 h robust stability. Interestingly, it also demonstrates an excellent performance with the FE of 42.8% for NO3− solution as the nitrogen source. Specially, this strategy displays a broad universality for the synthesis of other amino acids. This work not only highlights the importance of hollow-structuring electrocatalyst towards upgrading wasted NOx species into amino acids, but also promotes the further development of electrosynthetic systems for high-valued N-containing organic chemicals. [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]