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C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K.

Green and highly selective synthesis of ammonia (NH3) via electrochemical reduction reaction of toxic nitrite (NO2−RR) in a neutral electrolyte is a feasible solution for energy and environmental issues. Dual‐nature electrocatalysts combining metal and metal‐derived materials are crucial for enhancing the selectivity parameter and efficacy of this reaction. Here, Pd‐, Pt‐, Ru‐, and Ir‐decorated Co3(PO4)2 (CoPi) composites with a robust metal–support interaction are obtained via the one‐pot pulsed laser ablation in liquid method. Among the designed composites, Ir–CoPi affords ≈100% Faradaic efficiency, mass balance, and selectivity toward NH3 product at sufficiently low potentials. Further, it affords the highest NH3 yield rate of 19.13 mg h−1 cm−2 with 78.1% removal of toxic NO2− with a rate constant kapp = 0.31 mm min−1 under −1.6 V versus Ag/AgCl. In situ experiments and theoretical investigations reveal the underlying mechanisms responsible for this outstanding performance of Ir–CoPi, which can be accredited to the generation of specific active sites on the Ir component. Insights derived from the evolving intermediate reactive species provide new opportunities for large‐scale NH3 production through electrochemical techniques, density functional theory calculations, and the improvement of the corresponding industrial processes. [ABSTRACT FROM AUTHOR]

Here, furfural oxidation was performed to replace the kinetically sluggish O2 evolution reaction (OER). Pt‐Co3O4 nanospheres were developed via pulsed laser ablation in liquid (PLAL) in a single step for the paired electrocatalysis of an H2 evolution reaction (HER) and furfural oxidation reaction (FOR). The FOR afforded a high furfural conversion (44.2%) with a major product of 2‐furoic acid after a 2‐h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0‐M KOH/50‐mM furfural electrolyte. The Pt‐Co3O4 electrode exhibited a small overpotential of 290 mV at 10 mA cm−2. As an anode and cathode in an electrolyzer system, the Pt‐Co3O4 electrocatalyst required only a small applied cell voltage of ∼1.83 V to deliver 10 mA cm−2, compared with that of the pure water electrolyzer (OER∥HER, ∼1.99 V). This study simultaneously realized the integrated production of energy‐saving H2 fuel at the cathode and 2‐furoic acid at the anode. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K. [ABSTRACT FROM AUTHOR]

The biochemical reduction of nitrite (NO 2 - ) ions to ammonia (NH 3 ) requires six electrons and is catalyzed by the cytochrome c NO 2 - reductase enzyme. This biological reaction inspired scientists to explore the reduction of nitrogen oxyanions, such as nitrate (NO 3 - ) and NO 2 - in wastewater, to produce the more valuable NH 3 product. It is widely known that copper (Cu)-based nanoparticles (NPs) are selective for the NO 3 - reduction reaction (NO 3 - RR), but the NO 2 - RR has not been well explored. Therefore, we attempted to address the electrocatalytic conversion of NO 2 - to NH 3 using Cu@Cu 2 O core-shell NPs to simultaneously treat wastewater by removing NO 2 - and producing valuable NH 3 . The Cu@Cu 2 O core-shell NPs were constructed using the pulsed laser ablation of Cu sheet metal in water. The core-shell nanostructure of these particles was confirmed by various characterization techniques. Subsequently, the removal of NO 2 - and the ammonium (NH 4 + )-N yield rate were estimated using the Griess and indophenol blue methods, respectively. Impressively, the Cu@Cu 2 O core-shell NPs exhibited outstanding NO 2 - RR activity, demonstrating a maximum NO 2 - removal efficiency of approximately 94% and a high NH 4 + -N yield rate of approximately 0.03 mmol h -1 .cm -2  at -1.6 V vs. a silver/silver chloride reference electrode under optimal conditions. The proposed NO 2 - RR mechanism revealed that the (111) facet of Cu favors the selective conversion of NO 2 - to NH 3 via a six-electron transfer. This investigation may offer a new insight for the rational design and detailed mechanistic understanding of electrocatalyst architecture for the effective conversion of NO 2 - to NH 4 + ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The induced circular dichroism (ICD) of phenol complexed with ( R )-(-)-2-butanol [PhOH-(-)BOH] in a supersonic jet is investigated using resonant two-photon ionization circular dichroism (R2PICD) spectroscopy. The R2PICD spectrum of PhOH-(-)BOH exhibits nonzero ICD bands near the absorption region of bare PhOH, where (-)BOH is transparent. Two different conformers containing a single hydrogen bond between PhOH and (-)BOH are identified using ultraviolet-ultraviolet hole-burning and infrared ion-dip spectroscopy combined with quantum theoretical calculations. The ICD values of the two conformers are similar to each other. To understand these similar ICD effects of the conformers, the geometrical asymmetry of the PhOH moiety bound to (-)BOH and the coupling strength of the electric transition dipole moments between PhOH and (-)BOH are estimated. Comparing the ICD values of PhOH-(-)BOH with those of PhOH-(-)-l-methyl lactate in the previous report [ Hong , A. ; J. Phys. Chem. Lett. 2018 , 9 , 476 -480 ], we investigate the physical properties that may govern the differences of the ICD values between the two complexes.