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Oxime ethers are attractive compounds in medicinal scaffolds due to the biological and pharmaceutical properties, however, the crucial and widespread step of industrial oxime formation using explosive hydroxylamine (NH2OH) is insecure and troublesome. Herein, we present a convenient method of oxime ether synthesis in a one‐pot tandem electrochemical system using magnesium based metal‐organic framework‐derived magnesium oxide anchoring in self‐supporting carbon nanofiber membrane catalyst (MgO‐SCM), the in situ produced NH2OH from nitrogen oxides electrocatalytic reduction coupled with aldehyde to produce 4‐cyanobenzaldoxime with a selectivity of 93 % and Faraday efficiency up to 65.1 %, which further reacted with benzyl bromide to directly give oxime ether precipitate with a purity of 97 % by convenient filtering separation. The high efficiency was attributed to the ultrafine MgO nanoparticles in MgO‐SCM, effectively inhibiting hydrogen evolution reaction and accelerating the production of NH2OH, which rapidly attacked carbonyl of aldehydes to form oximes, but hardly crossed the hydrogenation barrier of forming amines, thus leading to a high yield of oxime ether when coupling benzyl bromide nucleophilic reaction. This work highlights the importance of kinetic control in complex electrosynthetic organonitrogen system and demonstrates a green and safe alternative method for synthesis of organic nitrogen drug molecules. [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]

Detection of ppb-level formaldehyde at low temperatures is a great pursuit for metal oxide semiconductor sensors. To realize this goal, metal organic framework (MOF) derived hollow hexagonal prism with surface-grown nanofibers were successfully prepared and modified using quantum dots, affording a 3D/0D heterojunction with excellent sensing performance. The CdS@c/h-In 2 O 3 -2 hollow hexagonal prism exhibits outstanding sensing properties (107.37 for 100 ppm), ideal selectivity, and low detection limit (160 ppb) at 160 °C. Moreover, the possible formation mechanism of the hollow hexagonal prism and endogenous phase-homojunction are proposed. Further, an insight into the synergistic enhancement of endogenous phase-homojunction and heterojunction is presented, including the gas diffusion, density functional theory (DFT) calculations, and resistance-controlled mechanism. The distinguished HCHO-sensing performance can be attributed to MOF-derived endogenous phase-homojunction, 3D/0D heterostructure, hollow morphology, and confined internal space, which ultimately synergize to strengthen the adsorption and electron transfer behavior of oxygen and HCHO molecules. Overall, this work provides new insights into the feasible strategy and theoretical viewpoint concerning high-performance HCHO sensors. [Display omitted] • A promising 3D/0D hollow hexagonal prism decorated with QDs were prepared. • The CdS@c/h-In 2 O 3 exhibits excellent sensing behavior towards ppb-level HCHO. • An insight into synergistic enhancement of phase-homojunction and heterojunction is shown. • DFT revealed the adsorption behavior and electron transfer characteristics. • Homojunction, heterojunction and hollow morphology enhance performance. [ABSTRACT FROM AUTHOR]