We report nitrite-to-NO reduction using Mo(P^S^S)2 (1, where P^S^S = PhP(o-C6H4S-)2), and explore the protonation of the resulting anionic Mo(IV)-NO complex (2) as a potential for further transformations. In the absence of benzenethiol as an external reductant, both the molybdenum center and the phosphine donor in 1 serve as internal oxygen-atom acceptors, resulting in the formation of Mo(VI)-oxo (3), Mo(IV)-NO (2), and phosphoryl-ligated Mo(IV)-NO (4) complexes, all of which are structurally characterized. Notably, the anionic Mo(IV)-NO complex undergoes sulfur protonation, as demonstrated by the isolation of a rare S···H-N hydrogen-bonded intermediate [(NO)Mo(P^S^S)2][HLut] (5), and the protonated complex (P^S^S)Mo(NO)(P^S^SH) (6).

Reductive transformation of nitric oxide (NO) by heme proteins is critical for dissimilatory nitrate reduction to ammonium, a microbial nitrogen-conserving process. This study reports the complete reduction of bound NO to NH3 on a bimetallic FeMo platform through a protonation-hydride reduction strategy. Protonation of the μ-NO group generated a μ-NOH intermediate, which, upon reaction with HBpin, underwent simultaneous N-O bond cleavage and N-H bond formation to give a μ-NH imide. Subsequent transformations among nitride, imide, and amide were achieved via deprotonation/protonation and the additions of hydride, hydrogen atoms, and H2 provide molecular-level mechanistic insight into ammonia synthesis and nitrogenous-species interconversion.

Mn-doped Fe2O3 with the different Mn/Fe ratio (marked as XMn-Fe2O3, X = 1, 2, 3, 4) were prepared via a facile one-step hydrothermal method. The crystalline structure, morphology, and chemical state were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron Microscopy. The morphology of Mn doped Fe2O3 exhibited significant variations with Mn doping concentration and tended to form polyhedral structures. The photo-Fenton degradation activity and reusability of the synthesized catalysts for tetracycline removal were evaluated under visible light illumination. The results demonstrated that 2Mn-Fe2O3 achieved the higher removal tetracycline efficiency of 65% at 90 min, and with only slight performance degradation after four consecutive cycles times under identical conditions. Based on the radical trapping experiments and electron paramagnetic resonance analysis, the enhanced photo-Fenton activity might be attributed to the following factors: on the one hand, the appropriate concentration of Mn doping reduces the bandgap of Fe2O3, suppresses electron/hole recombination and enhances photoexcited charge carrier mobility. On the other hand, the synergistic interaction between Mn and Fe ions can promote the activation of hydrogen peroxide to generate more & centerdot;OH radicals, while the Mn & sup3;(+)/Mn(2+)and Mn4+/Mn & sup3;(+) redox cycle accelerates the Fe & sup3;(+)/Fe2+ cycle. [GRAPHICS]

Here, we report a C(sp 2 )−C(sp 2 /sp) coupling reaction driven by charge transfer interaction. Due to the strong intermolecular noncovalent interaction, an essential electron donor-acceptor (EDA) complex is formed, confirmed solidly by absorption spectra, 1 H NMR and single crystal X-ray diffraction. The EDA complex lowers the activation barrier ( E a =9.17 kcal/mol) and facilitates the formation of the C−C bond, which is the rate-limiting step revealed by H/D and 12 C/ 13 C KIE studies. Kinetic investigations reveal that the reaction is a second-order reaction. Furthermore, high-level theoretical calculations support the proposed mechanism. The mono- and di-substituted products were obtained by varying the reaction conditions. A series of structurally diverse and novel second near-infrared (NIR-II) fluorophores based on benzo[1,2-c : 4,5-c’]bis([1,2,5]thiadiazole) (BBTD) were synthesized by utilizing this coupling reaction.

We report a novel bimetallic approach utilizing cooperative Fe─Al reactivity for N2 activation on the Cp*Fe(1,2-Cy2PC6H4AlEt) platform, effectively capturing two N2 molecules through intermolecular Fe─N≡N─Al coordination. Characterizations of the N2-bridged Fe─Al dimer (2) using Mössbauer spectroscopy coupled to density functional theory (DFT) calculations reveals its electronic structure as a resonance hybrid between Fe(II)-Al(I) and Fe(0)-Al(III). The flexible, covalent Fe─Al bonding facilitates the subsequent alkylation of the Al site with nBuLi, leading to the formation of a dinitrogen-lithiated complex (3) that enables the silylation of the terminal N atom. Our findings highlight the significance of leveraging Fe─Al effects as an electron buffer to achieve facile N2 activation.

The high Li+ desolvation energy barrier causes sluggish kinetics and uncontrolled dendrite growth, leading to severe solid electrolyte interface (SEI) instability and hindered ion transport across lithium-metal anodes (LMAs), which remains a major barrier to commercialization. Herein, a Lewis-based N/O dual-functional covalent organic polymer (COP-DQCC) with abundant carbonyl components was designed and integrated into a commercial polypropylene (PP) separator. Experimental and theoretical calculations show that the high lithiophilicity of Lewis base N/O atoms enhances lithium salt dissociation, promotes Li+ desolvation from the solvation shell, reduces solvent molecule transport, simplifies the solvated structure of Li+, lowers ion diffusion activation energy, and accelerates Li+ migration. Additionally, the suitable pore size of the triazine composite carbonyl organic unit regulates the electroplating/stripping behavior of LMA. In situ optical microscopy reveals that the COP-DQCC layer effectively inhibited dendrite growth. Time-of-flight secondary ion mass spectrometry further confirms that the COP-DQCC layer promotes the formation of a stable LiF-rich SEI layer, regulates Li+ transport and uniform deposition. Ultimately, the Li/COP-DQCC@PP/Li symmetric cell demonstrated stable cycling for over 2400 h at 1.0 mA cm-2/1.0 mAh cm-2, maintaining a low overpotential, and continued stable cycling for over 900 h at 4.0 mA cm-2/4.0 mAh cm-2. Additionally, the LiFePO4/COP-DQCC@PP/Li cell shows remarkable cycling stability, retaining 84.6% of its capacity after 1200 cycles at 1.0 C, and excellent cycling performance at higher loading of LiFePO4. This work highlights the development of a durable, dendrite-free anode, offering significant potential for advancing high-energy-density LMAs.

Two pentamethylcyclopentadienyl molybdenum(V) chloride complexes bearing mercaptobenzothiazolate and phosphaneyl-benzenethiolate ligands are synthesized and structurally characterized to feature a capped octahedral coordination geometry. Electron paramagnetic resonance investigations combined with density functional theory calculations reveal that their sole unpaired electrons are predominantly localized in the Mo dxy$d_{x y}$ centered molecular orbital.

We report an efficient bimetallic Mo(IV)Fe(II) electrocatalyst that achieves highly selective nitrite-to-NO reduction. This catalyst demonstrates exceptional performance, with a record turnover frequency (TOF) of ∼103 s-1 and a Faradaic efficiency of 93.8%. Mechanistic studies integrating experimental and DFT analyses reveal that the Mo(IV) center preferentially binds NO over the Fe(II) site, preventing the catalytic cycle from terminating at a stable ferrous nitrosyl species. The synergistic interplay between the Fe and Mo centers enhances nitrite dynamic coordination and facilitates reductive N-O bond cleavage, highlighting the critical role of bimetallic synergism in lowering energy barriers and driving demanding exergonic reaction steps involving electron and proton transfer.

Porous carbon nanomaterials derived from waste biomass have attracted a great deal of attention as high-performance nonprecious metal electrocatalysts for the oxygen reduction reaction (ORR). However, the production of porous carbon nanocatalysts usually requires a high temperature and a long time. Here, we propose a fast low-temperature strategy to obtain nonmetal and transition metal codoped porous graphene with a tunable hole structure from waste seed husk via a triple KCl/LiCl/ZnCl2 molten salt system. The codoped porous graphene exhibited a large specific surface area, sufficient microporous/mesoporous channels, and equally distributed elements, resulting in excellent catalytic activity, long-term stability, and methanol tolerance for ORR in alkaline media. In particular, the prepared PG-600-N,Co catalyst retains 97.1% of its initial current density after a chronoamperometric response test of 65 000 s, which is much better than the commercial Pt/C catalyst. Moreover, PG-600-N,Co can be applied as an anode in lithium-ion batteries (LIBs) and exhibits outstanding performance. In particular, it shows a specific capacity of 404 mAh g-1 after 100 cycles at a current density of 1 A g-1. Our work offers a feasible massive synthesis of regulated codoped porous graphene as efficient ORR nanocatalysts and anodes for LIBs.

The construction of heterojunction photocatalysts with high efficiency for activating peroxymonosulfate (PMS) to degrade organic pollutants has aroused wide concern. Herein, a novel MIL-53(Fe)/SnS2 Z-scheme heterojunction photocatalyst was successfully prepared by solvothermal method, which was used for the degradation of rhodamine B (RhB) in the catalyst/PMS system under visible light irradiation. The results showed that the MIL53(Fe)/SnS2-3 % (3 % is the mass ratio of SnS2 to MIL-53(Fe)) displayed the highest activity reaching a RhB (10 mg/L, 100 mL) removal rate of 85.6 % within 60 min with catalyst and PMS dosage of 0.1 and 0.1 g/L, respectively. The corresponding reaction rate constant exceeded that of MIL-53(Fe) and SnS2 by a factor of 1.39 and 6.39 times, respectively. The enhanced performance of MIL-53(Fe)/SnS2/PMS system can be attributed to the Z-scheme heterojunction formed between MIL-53(Fe) and SnS2, which inhibits the recombination of photogenerated electron-hole pairs. The PMS activation mechanism by MIL-53(Fe)/SnS2 was proposed based on the detailed catalyst characterization, degradation efficiency tests, electron paramagnetic resonance and radical quenching experiments. Furthermore, the MIL-53(Fe)/SnS2 exhibited good stability and suitability for different environmental conditions. This work provides a valuable guide for the development of Fe-based metal-organic frameworks (MOF) composites for photoactivation of PMS to remove organic dyes in aquatic environment.

The immobilization of powdery photocatalysts has always been a key technology for its practical application in waste-water purification. In this study, we successfully prepared carbon cloth-supported Co3O4/Ag3PO4 composites with high photocatalytic activity and good recyclable property for photodegradation of rhodamine B under visible light irradiation. The results show that the carbon cloth-supported Co3O4/Ag3PO4 composites exhibits higher photocatalytic activity than that of carbon cloth-supported Ag3PO4. Density functional theory (DFT) calculations and X-ray photoelectron spectroscopy (XPS) results further confirm that the successful construction of the S-scheme heterojunction is the reason for the composite's efficient charge separation and strong oxidation capability. Moreover, the Co3O4 nanoneedles and carbon fibers provide high speed charge transfer channels for photo-generated electrons, leading to lower recombination rate of electron-hole pairs and higher photocatalytic performance of the composite photocatalyst. Our strategy can be extended to fabricate many other recyclable carbon cloth-supported photocatalysts with high performance that shows promising potential applications in wastewater treatment.

Continuous carbon fibre–reinforced aluminium matrix composites (Cf/Al) possess superior properties including high strength and low density and are extensively used in fields including aerospace, defence, and industrial facilities. In this paper, simulation and experimental research on single-diamond-grain grinding of unidirectional Cf/Al composites were carried out. The removal mechanism of carbon fibres under different fibre angles was analysed, and on this basis, the influence of fibre angles and grinding parameters on the machined surface roughness Sa was explored. The analysis shows that under different fibre angles, the main defect forms of fibres include fibre fracture, fibre exposure, and fibre debonding. Moreover, the difference in fibre angle α can also lead to differences in the fibre fracture surface. Further research on surface quality found that the closer the α angle is to 90°, the larger the Sa will be. With the grinding depth ap increases, the Sa increases and the surface topography of Cf/Al composites deteriorates. With the wheel speed vs increases, the Sa decreases, and the surface topography of Cf/Al composites improves.

A three-dimensional (3D) flower-like Sn-doped BiOCl hierarchical structure constructed from nanoparticles has been successfully prepared using SnS2 nanoflowers as sacrificial templates. The morphology and microstructures of the samples were systematically characterized combined with density functional theory (DFT) calculations, and the photocatalytic activity of the samples was investigated by degradation of tetracycline hydrochloride (TCH) under visible light irradiation. The intermediate products generated in the degradation pathway of TCH were studied by liquid chromatography-mass spectrometry technology. The results showed that the 3D flower-like Sn-doped BiOCl exhibits an enhanced performance compared with pure BiOCl, which can be attributed to the increased specific surface area induced by smaller nanoparticles. Meanwhile, Sn-doping promoted the absorption of visible light and separation of photogenerated charge carriers. Further studies showed that the micron-sized Sn-doped BiOCl flower can be much more easily separated from the suspension only by natural sedimentation and re-used. Based on the comprehensive results of DFT calculations, transient photocurrent, electrochemical impedance spectroscopy and free radical capture experiments, a photocatalytic mechanism for the degradation of TCH by the Sn-doped BiOCl photocatalyst was proposed. Our strategy can be extended to the synthesis of many other photocatalysts with hierarchical structures that show high performance for removing antibiotics in wastewater.

We report a well-defined multifunctional iron catalyst, Cp*Fe(Ph2PN = C5H4N), that promotes the rearrangement of β,γ-unsaturated ketones, esters, and amides to their α,β-isomers, enabling regioselective C═C reductive deuteration. This iron-catalyzed protocol showcases the synthesis of a diverse range of α,β-dideuterated organic compounds, demonstrating broad substrate compatibility under mild conditions. Mechanism studies provide insights into the C═C bond relocation and cooperative D2 activation.

The development of effective methods for the synthesis of supported photocatalysts instead of dispersive powdery photocatalysts has received great attention. Herein, a flexible visible -light -driven carbon cloth -supported Co 3 O 4 /AgIO 4 composites was successfully prepared by combining electrodeposition and chemical coprecipitation method. After 40 min of visible -light illumination, 99.2 % of the rhodamine B can be degraded by carbon cloth -supported Co 3 O 4 /AgIO 4 composites with electrodeposition duration of 50 min, showing a highest reaction rate constant of 10.5 x 10 -2 min -1 which exceeds that of CC/Co 3 O 4 and CC/AgIO 4 by a factor of 58.39 and 2.67 times, respectively. The band structures of the samples were studied by valence band X-ray photoelectron spectroscopy, ultraviolet photoemission and theoretical calculations. The capture experiments confirmed that positive holes and the superoxide radicals are two main reactive species participating in the degradation of rhodamine B. The excellent photocatalytic reactivity can be attributed to the successful construction of S -scheme heterojunction between Co 3 O 4 and AgIO 4 . The Co 3 O 4 /AgIO 4 heterojunction not only inhibited the rapid recombination of charges but also reserved the oxidation and reduction ability of the holes in the valence band of AgIO 4 and electrons in the conduction band of Co 3 O 4 . The work is of great significance in the development of carbon cloth -supported photocatalysts with good recyclability for practical applications of wastewater treatment.

Catalytic activation of peroxymonosulfate (PMS) is one of the important research areas in the development of advanced oxidation technology for wastewater treatment. At present, the development of high-performance catalysts for PMS activation has become a research hotspot. Herein, (Cu+ decorated g-C3N4)/Bi2WO6 ((Cu+/g- C3N4)/Bi2WO6) composite was prepared successively by calcination and solvothermal method, which was used in visible light-assisted PMS activation for the degradation of rhodamine B (RhB). The construction of S-scheme heterojunctions between Cu+ decorated g-C3N4 and Bi2WO6 facilitated the activation of PMS, leading to a RhB degradation ratio of 98.46 % within 50 min. The corresponding reaction kinetic was significantly improved by a factor of 2.32 and 7.94 compared with that of CCN and BWO, respectively. The enhanced performance of the (Cu+/g-C3N4)/Bi2WO6 can be attributed to the successful construction of S-scheme heterojunction, which facilitates the separation of photogenerated carriers and accelerates the PMS activation to produce abundant active species. Furthermore, the (Cu+/g-C3N4)/Bi2WO6 composites exhibit strong stability and reusability following three cycles. In addition, the intermediates produced during the RhB degradation process were investigated by liquid chromatograph mass spectrometer (LC-MS). This study provides a new insight into the preparation of Sscheme photocatalysts for the photocatalytic-PMS activation system that will achieve efficient removal of dyes from wastewater.

Carbon dioxide(CO2)serves as a sustainable carbon source for building biomass,fossil fuels,and organic chemicals.Converting CO2 into value-added chemicals or fuels is an ideal approach to achieve carbon cycling.The reduction and conversion of CO2,a pivotal aspect of Cl chemistry,have long been a subject of intense research interest.Previous studies have demonstrated that through transition metal catalysis,hydrogen,boranes,and silanes(E—H,E=H,B or Si)act as effec-tive reducing agents to transform CO2 into a range of Cl chemicals,such as formate,formaldehyde,and methanol.Over the past decade,research focus in this field has shifted towards utilizing cost-effective metals as catalysts for selective CO2 reduc-tion.A comprehensive review of homogeneous iron-catalyzed CO2 reduction using E—H is presented,emphasizing reaction mechanisms and selectivity.

The reservoir quality of tight sandstone is usually affected by pore throat structures, and understanding pore throat structures and their fractal characteristics is crucial for the exploration and development of tight sandstone gas. In this study, fractal dimensions of pore throat structures and the effect of diagenesis on the fractal dimension of tight sandstone sweet spot in Huagang Formation, Jiaxing area, East China Sea Basin were studied by means of thin sections, scanning electron microscopes, X-ray diffraction analysis, scanning electron microscope quantitative mineral evaluation, and high pressure mercury injection experiments. The results show that the total fractal dimension ranges of type I, type II, and type III sweet spots were 2.62–2.87, 2.22–2.56, and 2.71–2.77, respectively. The negative correlation between total fractal dimensions, porosity, and permeability of type I sweet spots was different from those of type II and type III sweet spots. The negative correlation between total fractal dimensions of type II and type III sweet spots and maximum mercury saturation, average pore throat radius, and skewness were significant, whereas the correlation between total fractal dimensions of type I sweet spots, and maximum mercury saturation, average pore throat radius and skewness were not significant. The positive correlation between the total fractal dimensions of type II and type III sweet spots and the relative sorting coefficient, displacement pressure, and efficiency of mercury withdrawal were significant, whereas the correlation between the total fractal dimension of type I sweet spots and relative sorting coefficients, displacement pressures and efficiency of mercury withdrawal were not significant. The effect of diagenesis on fractal dimensions was investigated. Compaction reduced the pore space of tight sandstone and increased fractal dimensions. Quartz cementation and calcite cementation blocked pores and throats, reduced pore space, and increased fractal dimensions. Chlorite coat can inhibit compaction, protect pore throat structures, and maintain fractal dimensions. Most clay minerals filled primary pores and secondary pores and increased fractal dimensions. Dissolution increased the pore space of tight sandstone and decreased the fractal dimensions of the pore throat structures. The pore throat structures of type I sweet spots were mainly composed of macropores, mesopores, transitional pores, and micropores, and the fractal dimension of type I sweet spots was chiefly controlled by chlorite coat formation, dissolution, and a small amount of compaction. This study provides a reference for pore throat structure and fractal dimension analysis of tight sandstone sweet spots.