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To tackle the challenge of ground-level ozone pollution, this study proposed a potential catalytic design approach for ozone decomposition using Cu–Mn bimetallic oxide. This approach is grounded in an understanding of the intrinsic reactivity for catalyst and incorporates a novel potassium-driven low-temperature oxidation process for catalyst synthesis. The research highlights the creation of a highly reactive Cu–Mn oxide phase with extensive defect coverage, leading to significantly increased reaction rates. It also identifies the MnO2(100) facet as a crucial active phase, where oxygen vacancies simultaneously enhance O3 adsorption and decomposition, albeit with a concurrent risk of O2 poisoning due to the stabilization of adsorbed O2. Crucially, the incorporation of Cu offsets the effects of oxygen vacancies, influencing conversion rates and lessening O2 poisoning. The synergistic interplay between Cu and oxygen vacancies elevates the performance of the defect-rich Cu–Mn oxide catalyst. By combining computational and experimental methods, this study not only advances the understanding of the Cu–Mn oxide system for ozone decomposition but also contributes valuable insights into developing more efficient catalysts to mitigate ozone pollution. [ABSTRACT FROM AUTHOR]

Perovskites refer to ceramic materials with an ABO 3 structure. The optimization of synthesis parameters and material composition can enhance the catalytic efficiency in various chemical reactions, such as dry methane reforming. In order to highlight the differences in the catalytic properties, this study aims to compare three synthesis methods (citrate, auto-combustion and Pechini) for a same perovskite formulation namely SrZr 0·5 Ni 0·4 Fe 0·1 O 3. The crystal structure and reducibility profile are determined by XRD and TPR experiences respectively. Surface properties and composition are identified by chemisorption tests (allowing the study of basicity and nickel dispersion) and XPS analyses, respectively. Isothermal catalytic experiences from 600 to 750 °C, under atmospheric pressure and for a WHSV of 40 L / h. g together with stability tests for 25 h at 750 °C were conducted. The outcomes show the importance of properly choosing the perovskite preparation methods in order to achieve the desired surface, structural and reactivity properties. [Display omitted] • Comparison of synthesis methods for substituted perovskites SrZrO3 with Ni and Fe. • Utilisation of citrate, auto-combustion and Pechini methods. • Dry methane reforming considered as a test reaction. • Effect of the method on surface properties, crystal structure and reactivity. [ABSTRACT FROM AUTHOR]

Herein, we report the first example of Rh-catalyzed C(sp²)-H difluoroallylation of α,β-unsaturated amides with 3-bromo-3, 3-difluoropropene under mild conditions. The features of this protocol for difluoroallylation are unprecedented vinylic substrates, ethanol as a green solvent, good functional group and air compatibility, and scale-up synthesis with low catalyst loading. [ABSTRACT FROM AUTHOR]

Metal-based catalysts play an essential role in organic chemistry and the chemical industry. This research designed and successfully synthesized a pillar-layered metal–organic framework (MOF) with the urea linkers, namely Basu-HDI, as a novel and efficient heterogeneous catalyst. Various techniques such as FT-IR, EDX, elemental mapping, SEM, XRD, BET, and TGA/DTA studied its structure and morphology. Then, we investigated the synthesis of new 1,8-naphthyridines utilizing Basu-HDI in mild conditions via a one‐pot, three‐component tandem Knoevenagel/Michael/ cyclization/anomeric-based oxidation reaction. Final products were achieved by anomeric-based oxidation without employing an oxidation agent. Remarkably, this tandem process gave a good range of new 1,8-naphthyridines with high yields in a short reaction time. The pure products were confirmed by FT-IR, 1H NMR, 13C NMR, and mass spectrometry techniques. Moreover, the introduced catalyst showed good efficiency and stability and can be reused four times without significantly reducing efficiency. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is an important raw material in the chemical industry, but the synthesis of NH3 by the traditional Haber‐Bosch process will increase the carbon footprint. Therefore, it is necessary to develop sustainable routes for NH3 production. New NH3 production schemes, including nitrogen reduction (N2RR), nitrite reduction (NO2RR), and nitrate reduction (NO3RR), have been proposed. Porphyrins and phthalocyanines are macrocyclic compounds with a central metal ion coordinated with nitrogen. The metal centers in these catalysts play a crucial role in binding and activating nitrogen, nitrite, and nitrate. Their unique structure allows for effective electron transfer and catalytic activation in NH3 synthesis. Recently, metal porphyrin and phthalocyanine based catalysts have been demonstrated to be efficient in catalyzing N2RR, NO2RR, and NO3RR. Unfortunately, there is no review focusing on such macrocyclic catalysts for the electrocatalytic synthesis of NH3. In this review, we discuss the electrocatalytic reduction performances and summarize the key factors and reaction mechanisms that affect the catalytic performance of metal porphyrin and phthalocyanine based catalyst systems. This review helps to design more effective new electrocatalysts for NH3 synthesis. [ABSTRACT FROM AUTHOR]

The hydrogenation of acetylene to ethylene is of great industrial interest. Achieving both high selectivity and high conversion of acetylene to ethylene via semi‐hydrogenation is quite challenging. Bimetallic catalysts offer opportunities to selectively control reaction pathways by altering the electronic and geometric properties of active sites on the catalyst surface. Recent advancements in the synthesis of bimetallic catalysts enabled the creation of random alloys, intermetallics, segregated structures, or single‐site alloys with precision. These catalysts could be tailored for semi‐hydrogenation of acetylene by tuning the features including adsorption energy, active site isolation, and the d‐band center. Modern machine learning tools are also helpful for catalyst design. In this article, an overview of the conceptual advances in the design aspects of bimetallic catalysts, advances and challenges involved in the acetylene semi‐hydrogenation, has been presented. [ABSTRACT FROM AUTHOR]

Iron‐based catalysts play an important role in the ammonia industry. As one of the most abundant iron minerals, Fe3O4 containing FeII and FeIII sites is widely distributed in the earth's crust and even on exoplanets, theoretically giving it both economic and catalytic potentials in ammonia synthesis. However, in the absence of specific active co‐catalyst and harsh conditions, Fe3O4 is impossible to achieve ammonia synthesis alone. Here, we designed to activate the relatively inert FeII and FeIII sites in Fe3O4 with a third FeIII site inlayed in a coordination framework (MIL‐101(Fe)) to achieve the unpresented multi‐site collaborative catalysis. In‐depth mechanism study confirmed the roles of three different Fe sites in N2 activation, H2 activation, and product transfer, respectively. Efficient N2−H2 activation to NH3 on the Fe3O4‐based catalytic system has been achieved at extremely mild conditions. Our research provides a theoretical basis and a new strategy for designing efficient non‐noble metal‐based ammonia synthesis catalyst with minimized energy consumption. [ABSTRACT FROM AUTHOR]

Discovery of novel antimicrobial drugs is one of the hottest topics in the field of medicinal chemistry. An efficient and catalyst free synthesis of novel fluorinated 5‐substituted 1,2,4‐oxadiazole‐3‐yl benzoxazole derivatives is described. A series of novel compounds have been synthesized and characterized by different spectroscopic techniques such as FTIR, 1H NMR, 13C NMR, and LCMS. When tested for antibacterial activity, the synthesized benzoxazole derivatives exhibited outstanding to good activities in comparison to the conventional medications. Moreover, the theoretical forecasts grounded in molecular docking against microbial DNA gyrase may offer a glimpse into the conceivable mode of operation and establish a connection between the detected antimicrobial efficacy and the binding affinity, illuminating particular thermodynamic (bonded and nonbonded) interactions that regulate the activity. The produced compounds also exhibited promising qualities to develop into viable oral medication candidates when their absorption, distribution, metabolism, and excretion were examined. In summary, the research proposes that these novel compounds have emerged as interesting contender for the development of next generation antimicrobial drugs. Our protocol demonstrates broad substrate scope, dramatic decrease of synthesis time, and energy consumption with excellent yields. [ABSTRACT FROM AUTHOR]

This study presents the synthesis and characterization of a novel nano‐magnetic catalyst, Fe3O4@SiO2‐APA‐amide/imid‐NiCl2, designed for the efficient production of 4H‐pyrimido[2,1‐b]benzothiazole derivatives under environmentally friendly, solvent‐free conditions. The catalyst combines magnetic Fe3O4 nanoparticles with a silica shell and functionalized amide and imidazole groups, which enhance its catalytic activity and stability. By optimizing the reaction conditions, we achieved high yields of the target compounds while minimizing the environmental impact. The catalyst's magnetic properties facilitate easy separation and recovery, making it an attractive option for sustainable organic synthesis. The successful synthesis of the catalyst was confirmed through comprehensive characterization techniques, including X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The results demonstrate that Fe3O4@SiO2‐APA‐amide/imid‐NiCl2 is a highly effective and reusable catalyst for the environmentally friendly synthesis of biologically relevant pyrimido[2,1‐b]benzothiazole derivatives, contributing to the advancement of green methodologies in organic chemistry. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs), featuring highly uniform active sites, tunable coordination environments, and synergistic effects with support, have emerged as one of the most efficient catalysts for various reactions, particularly for electrochemical CO2 reduction (ECR). However, the scalability of SACs is restricted due to the limited choice of available support and problems that emerge when preparing SACs by thermal deposition. Here, an in situ reconstruction method for preparing SACs is developed with a variety of atomic sites, including nickel, cadmium, cobalt, and magnesium. Driven by electricity, different oxygen‐containing metal precursors, such as MOF‐74 and metal oxides, are directly atomized onto nitrogen‐doped carbon (NC) supports, yielding SACs with variable metal active sites and coordination structures. The electrochemical force facilitates the in situ generation of bonds between the metal and the supports without the need for additional complex steps. A series of MNxOy (M denotes metal) SACs on NC have been synthesized and utilized for ECR. Among these, NiNxOy SACs using Ni‐MOF‐74 as a metal precursor exhibit excellent ECR performance. This universal and general SAC synthesis strategy at room temperature is simpler than most reported synthesis methods to date, providing practical guidance for the design of the next generation of high‐performance SACs. [ABSTRACT FROM AUTHOR]

This study investigated the development and optimization of sol–gel synthesized Ni/ZrO2-Al2O3 catalysts, aiming to enhance the decomposition efficiency of CF4, a potent greenhouse gas. The research focused on improving catalytic performance at temperatures below 700 °C by incorporating zirconium and tungsten as co-catalysts. Comprehensive characterization techniques including XRD, BET, FTIR, and XPS were employed to elucidate the structural and chemical properties contributing to the catalyst's activity and durability. Various synthesis ratios, heat treatment temperatures, and co-catalyst addition positions were explored to identify the optimal conditions for CF4 decomposition. The catalyst composition with 7.5 wt% ZrO2 and 3 wt% WO3 on Al2O3 (3W-S3) achieved over 99% CF4 decomposition efficiency at 550 °C. The study revealed that the appropriate incorporation of ZrO2 enhanced the specific surface area and prevented sintering, while the addition of tungsten further improved the distribution of active sites. These findings offer valuable insights into the design of more efficient catalysts for environmental applications, particularly in mitigating emissions from semiconductor manufacturing processes. [ABSTRACT FROM AUTHOR]

Research on synthetic methods for the preparation of oxazoles is an important issue among synthetic chemists because oxazole derivatives are structural subunits of various natural active products and are valuable synthetic and pharmaceutical precursors. In this research work, we constructed CuBr supported on surface of magnetic Fe3O4 nanoparticles modified with 6-(aminomethyl)nicotinic acid [Fe3O4@AMNA-CuBr nanocomposite] and evaluated its catalytic activity for the preparation of highly substituted oxazoles through one-pot three-component reactions of diphenylacetylene derivatives with aryl nitriles and water in PEG as the solvent. The results shown that the Fe3O4@AMNA-CuBr catalyst was used 8 times without significant decrease in catalytic activity. XRD and TEM analysis confirmed that the structure and morphology that the Fe3O4@AMNA-CuBr catalyst did not change after 8 runs. [ABSTRACT FROM AUTHOR]

Sulfamic acid-functionalized Zr-MOF-NH2 was used as an active acidic metal-organic framework catalyst for the synthesis of new 6-amino-5-(4-amino-2-oxo-2H-chromen) (AAOC) analogs via a one-step reaction between 2-hydroxy-5-(aryldiazenyl)benzaldehyde, 4-aminocumarin, and 6-amino-1,3-dimethyluracil or 6-amino-uracil in EtOH under reflux conditions. The resulting UiO-66-NHSO3H was characterized by employing different types of spectroscopic techniques such as XRD, BET, FESEM, EDS, FT-IR, and TGA. In addition, ease of procedure, short reaction time, and recycling of the catalyst without much change in the catalytic activity are the advantages of this method. [ABSTRACT FROM AUTHOR]

A modified two-step coprecipitation method has been formulated to prepare a series of model CuZnO/Al2O3 catalysts for methanol synthesis from syngas. Evaluation at industrially relevant condition showed slightly higher activity and much higher stability for model catalysts than for a commercial catalyst. Due to the same CuZn-binary precursor, the model catalysts had similar structural properties with large specific surface area and pore volume, small CuO crystallites and good reducibility, resembling that of the commercial catalyst. However, the model catalysts showed much better uniformity of alumina distribution, which accounted for their better performance. Strong positive correlation between the deactivation rate and the coefficient of variation of Al/Zn indicates the uniformity of alumina distribution plays an important role in determining stability. Specifically, CuZnO/Al2O3 catalysts with alumina distributed more uniformly had higher stability. This work demonstrated that the formulated modified two-step coprecipitation could provide excellent CuZnO/Al2O3 catalysts for industrial applications. Additionally, it also affords new clues for the development of even better industrial catalysts. [ABSTRACT FROM AUTHOR]

In this work hydrodeoxygenation of various lignin-derived model compounds and their mixture was studied over platinum catalysts based on porous aromatic frameworks (PAF) doped with Bronsted acid sites. Two catalysts, Pt-PAF-30-SO3H(5.0) and Pt-PAF-30-SO3H(7.5), with almost identical platinum loading of 5.1 and 4.7 wt. % but different sulfur concentration of 4.46 and 6.96 wt. % respectively, were synthesized using a method that allows to obtain highly uniform distribution of nanoparticles in the porous structure of the support. The HDO reaction pathways of lignin substrates with different structures were discussed, and the influence of the platinum source chosen for the synthesis of the catalyst on the activity and the selectivity of the latter was studied. We have demonstrated high stability of catalyst (for at least a 7 h reaction) and have confirmed the great activity of the Pt-PAF-30-SO3H(7.5) catalyst in HDO reactions with a large number of lignin bio-oil model compounds. Pt-PAF-30-SO3H(7.5) was also tested in the hydrodeoxygenation of a model mixture of aromatic substrates taken in proportions contained in lignin bio-oil. The selectivity to naphthenic hydrocarbons—products of the complete hydrodeoxygenation—was 54%. [ABSTRACT FROM AUTHOR]

Developing high-efficiency, high-stability, and low-cost deoxygenation and hydrocracking catalysts could be considered one of the most significant breakthroughs in catalytic hydroprocessing. The present study utilized aluminophosphate (AlPO4-18), a zeolite-like molecular sieve, as catalyst support for producing carbon-coated β-Mo2C, Ni3C, and WC nanoparticles. The synthesis used an incipient wetness impregnation followed by a temperature-programmed reduction-carburization approach which involved cracking a hydrocarbon gas, propane, in a hydrogen environment. The synthesis parameters were a 1:7 propane/hydrogen reductive-carburizing gas stream, 15 wt.% metal loading, an 800 °C carburization temperature ramped-up at a heating rate of 10 °C min−1, a 2-h holding time, and a 1-h holding time in hydrogen. The synthesized catalysts were characterized using thermogravimetry mass spectroscopy/temperature-programmed oxidation (TPO TG-MS), nitrogen physisorption at 77 K, X-ray diffraction (XRD), and transmission electron microscopy/energy-dispersive X-ray spectroscopy (TEM EDS). TPO TG-MS, nitrogen physisorption, TEM, and XRD characterization results proved that atomic carbon was successfully incorporated into the lattice interstitials, resulting in thermally stable, well-dispersed, crystalline and mesoporous β-Mo2C/AlPO4-18, Ni3C/AlPO4-18, and WC/AlPO4-18 nanoparticles. XRD analysis showed structural evolution during reduction-carburization, with average crystallite sizes of metal-containing particles of 8.2–9.22, 6.64–8.50, and 6.03–7.56 nm for β-Mo2C/AlPO4-18, Ni3C/AlPO4-18, and WC/AlPO4-18, respectively. These values did not significantly deviate from high-resolution TEM analysis. The surface areas of the nanoparticles were categorized in decreasing order as WC/AlPO4-18 > Ni3C/AlPO4-18 > β-Mo2C/AlPO4-18, with values of 193.79, 169.05, and 66.57 m2 g−1, respectively. In conclusion, these carbon-coated metal carbide nanoparticles with excellent thermal, structural, microscopic, and textural properties can be viable alternatives to noble metal catalysts for producing bio-jet fuel using the hydroprocessing pathway. [ABSTRACT FROM AUTHOR]

Herein, a modified synthesis method was presented and the effect of using an aqueous acetic acid solution in the process of synthesizing SQCOF was investigated. Adding a catalytic amount of aqueous solution of acetic acid as a co-catalyst has contributed to improving the quality of crystallinity. Effective parameters in the synthesis of SQCOF, including the concentration and volume of the co-catalyst and reaction solvent, were optimized. Then, the prepared SQCOF was used as a metal-free catalyst with Brønsted acid groups in the condensation reaction between 1,3-dicarbonyl compounds and primary amines. SQCOF was used under solvent-free conditions for the synthesis of enaminones at ambient temperature by mild manual grinding with a mortar and pestle and showed excellent catalytic performance in the above reaction. High performance and efficiency (62 to 96%), high TOF (833 to 1283 h−1), short reaction time, easy operation, minimizing the consumption of toxic organic solvents, absence of heavy metals in the framework and green conditions are the main advantages of this study. Also, SQCOF shows good chemical stability and recyclability (7 runs) and acts as an efficient catalyst in the synthesis of β-enaminones. [ABSTRACT FROM AUTHOR]

The selection of an appropriate preparation method is crucial to enhance catalytic performance and optimize the resources used in catalyst synthesis. Achieving improvements in conversion rates, desired product yields are essential for increasing interest and competitiveness in the industrial sector. This study aims to analyze the influence of the preparation method of Rh(1%)-Sn(4%)/γ-Al2O3 catalysts on the selective hydrogenation of oleic acid to oleyl alcohol. Results from temperature-programmed reduction (TPR), cyclohexane dehydrogenation (DHC), and X-ray photoelectron spectroscopy (XPS) clearly demonstrate that incorporating sodium borohydride in the preparation process results in a stronger interaction between Rh and Sn. The degree of interaction between Rh and Sn is significantly influenced by the catalyst preparation and activation method, with a strong interaction promoting selectivity towards the formation of oleyl alcohol. [ABSTRACT FROM AUTHOR]

Two novel complexes were synthesized by the reaction of benzothiazol‐pyrimidin‐2‐ylidene ligand (BTP) with Pd (II) and Fe (III) ions. A variety of various spectral and analytical methods (infrared, 1H/NMR, 13C/NMR, electronic spectra, CHN analyses, mass spectra, thermogravimetric analysis, and magnetic susceptibility) were used to characterize the investigated BTP ligand and its complexes. Correlation of experimental results with density functional theory calculation proves that the geometry of BTP‐Fe complex is octahedral, whereas BTP‐Pd complex is square planner. The catalytic effectiveness of BTP complexes were tested for three‐component condensation process under moderate and environmentally friendly reaction conditions. Moreover, the effects of different Lewis acid, basic, and ionic liquid catalysts, as well as solvent and catalyst dose on the catalytic reaction were investigated. Both catalysts demonstrated strong catalytic capability in the carefully regulated ideal reaction circumstances. Heterogeneous catalyst BTP‐Pd exhibited superior catalytic performance compared to homogeneous catalyst BTP‐Fe. All products were obtained in high TOF (turnover frequency) numbers in the presence of these catalysts, which indicate the high efficiency of these catalysts in the synthesis of dihydro‐7H‐5‐thia‐hexaaza‐s‐indacen‐6‐one derivatives. Moreover, the two catalysts' recycling and reusability in reactions were also investigated. Heterogeneous BTP‐Pd catalyst could be reused up to seven times with high efficiency, but the homogeneous catalyst (BTP‐Fe) could only be recycled up to four times. Furthermore, the mechanism of catalytic reaction was suggested and supported by DFT calculation. The simplicity, safety, stability, use of commercially available catalysts, quick reaction times, and excellent yields make it promising for future industrial use. [ABSTRACT FROM AUTHOR]

A novel binary transition metal oxide (NiFe2O4) nanosphere catalyst with a diameter of 500 nm has been synthesized by the hydrothermal reaction, which can efficiently catalyze the formation of hexagonal boron nitride nanotubes (BNNTs) with high‐yield and large aspect ratio. Based on the temperature dependence of the product phase composition and microstructure, combined with results generated using single‐component catalysts, the BNNTs formation process can be summarized as follows: NiFe2O4 reacts with NH3 to generate Fe0.64Ni0.36, which dissolves to form a liquid‐phase Ni‐Fe alloy at high temperatures, where the B component in the precursor and the N atom formed by the decomposition of NH3 diffuse on the surface of the Ni‐Fe alloy; when the concentration of B and N exceed the saturation threshold, hollow BNNTs containing catalyst at the tips are precipitated. The formation process is dominated by a vapor‐liquid‐solid mechanism with tip‐growth mode, where the synergistic catalytic effect of the Ni‐Fe binary system promotes a high yield of large aspect ratio BNNTs. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting is an environmentally friendly hydrogen production method that uses abundant renewable resources such as water and sunlight. While Titanium dioxide (TiO2) photocatalyst exhibits excellent properties, its high band gap limits absorption to ultraviolet (UV) irradiation, resulting in low photo conversion efficiency. This review explores various modification techniques aimed at enhancing the efficiency of TiO2 under visible light irradiation. Factors influencing the photocatalytic water splitting reaction, such as catalyst structure, morphology, band gap, sacrificial reagents, light intensity, temperature, and potential of Hydrogen (pH) are examined. This review also summarizes different catalyst synthesis methods, and types of photocatalytic reactors, and provides insights into quantum yield. Finally, the review addresses the challenges and future outlook of photocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Developing affordable and high‐performance catalysts for water electrolyzers and fuel cell devices is an emerging field of research aiming for their feasible implementation and thus addressing sustainable global energy demands. Accordingly, several catalytic systems have been developed for anodic oxidation reactions and cathodic reduction reactions. Specifically, more research attention has been focused on viable catalyst synthesis processes including design, choice of precursors, reaction conditions, and regulation steps for achieving desirable properties and performances. Intriguingly, biomass has been demonstrated as a promising precursor for the potential design of different carbon‐based catalysts for electrocatalytic oxidation/reduction reactions. In this review, the recent developments in using biomass precursors to derive different nanostructures are systematically discussed. The biomass‐derived catalysts especially applied for reduction reactions (hydrogen evolution and oxygen reduction reactions) are summarized, and the impact of various catalysts' engineering routes (incorporation of metals and nonmetals into the carbon structures) on the resulting structure–performance relationship is critically discussed. Further, this review highlights the performance of various biomass‐derived catalysts toward electrocatalytic reduction reactions that unveil the catalyst's intrinsic features such as selectivity, activity, and durability. The summarized results and the critical discussion will facilitate screening of the best biomass precursor, identifying suitable regulation strategies for accomplishing desirable properties, and thus advancing the next‐generation catalysts' developments. Further, the significance, challenges, and perspectives on biomass‐derived catalysts for electrocatalysis are comprehensively discussed. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) demonstrate high selectivity, maximal atom utilization, and unique active site configurations, establishing them as a rapidly expanding research field. Understanding the intrinsic relationship between structure and catalytic performance is crucial for the effective use of SACs in catalysis. However, providing a clear explanation of the coordination environment and intrinsic structural regulation of SACs remains a significant challenge for next‐generation renewable energy materials, especially in advanced oxidation and reduction processes critical for sustainable energy applications. This comprehensive review offers an in‐depth overview of the current progress and design of SACs, with a specific focus on precise synthesis, structural control, and the relationship between structure and performance. Furthermore, we elucidate the reaction mechanisms of various catalytic systems and the selective methods used to precisely synthesize and enhance catalytic reactions in the sustainable energy sector. Finally, this review explores the complex challenges in investigating and developing SACs and offers a perspective on solutions in advanced oxidation and reduction technologies for future research to overcome these challenges and achieve practical applications. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) manifest unique advantages in various aspects of catalysis but face challenges in atom‐economic synthesis. Solution reduction holds the promise of fast, continuous, and low‐cost synthesis of SACs, however, almost no chemical, electrochemical, or photochemical reduction can avoid the aggregation of metal atoms in solution. The issue becomes even tougher to composite dual‐atom metals together. Herein, a continuous‐flow solution plasma (CSP) method is developed, which utilizes high‐flux hydrated electrons, hydrogen radicals, and enhanced metal–support interaction, to achieve over 97% capture efficiency of metal precursors to fabricate CeO2‐based single‐atom Au, Rh, Pd, Ru, and Pt in only 0.03‐s residence time. Further, a programmed CSP synthesis of Au1Rh1/CeO2 and Au1Pd1/CeO2 dual‐atom catalysts is demonstrated. Under Xe lamp irradiation, Au1Rh1/CeO2 breaks room temperature constraints in CO conversion for the water–gas shift reaction with a T50 (the temperature at which 50% CO conversion occurs) of 298 K. The innovative CSP technology provides an atom‐economic approach to the continuous production of SACs using clean electricity without any additional reducing agent, paving the way for the programmed and green synthesis of SACs for industrial catalysis, energy conversion, and environment remedy applications. [ABSTRACT FROM AUTHOR]

The synthesis of K-promoted ZnO/ZnAl 2 O 4 nanocomposite catalyst for high temperature water gas shift (HT-WGS) via novel eco-friendly route using CO 2 as key reagent has been studied. The sodium and nitrate-free precursors of the Zn–Al spinels (ZnO/ZnAl 2 O 4) were successfully prepared by saturation of ZnO–AlOOH aqueous suspension with CO 2 , followed by thermal treatment and potassium deposition. The effect of the calcination temperature of precursor on the acid-base and textural properties, surface morphology and activity of catalysts was investigated. Nanocomposites calcined at 500–600 °C displayed higher basicity and specific surface area than samples calcined at temperature above 600 °C. At the same time, the high and stable activity of K–ZnO/ZnAl 2 O 4 catalysts toward HT-WGS was revealed for the nanocomposite. The catalysts exhibit high and stable activity and their selectivity is significantly higher than that of conventional systems for HT-WGS. Both at higher steam-to-carbon and also at lower H 2 O/C molar ratios, no methane formation was observed under HT-WGS conditions in the presence of ZnAl_X_K catalysts. [Display omitted] • Simple and eco-friendly route of catalyst synthesis using CO 2 as key reagent. • Great effect of the calcination temperature of ZnO–ZnAl 2 O 4 on textural properties and surface morphology. • Catalyst activity depends on the calcination temperature of ZnO–ZnAl 2 O 4 nanocomposite. • Higher selectivity of novel HT-WGS catalyst at lower steam-to-carbon ratio. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe synthesis of catalysts has gained specific concern due to their versatile applications in particular azo dye decolorization. In the current work, metallic nanoparticles (copper and silver) were In-situ biosynthesised using Allium sativum and Chondrilla juncea extract. The obtained Allium-copper oxide and Allium-silver oxide materials were analyzed using SEM, TEM, FT-IR, TGA-DTG, SEM, TEM, and XRD techniques. Allium peels had a rough surface, with nanoparticles equally distributed over it. The crystal structure of Allium peels was altered after the addition of CuO and AgO nanoparticles. The highest residual mass values in the prepared materials indicated that the metallic nanoparticles were, in situ, formed. The prepared materials had worse thermal stability than Allium peel powders. The azo dyes, Calmagite and Naphthol Blue Black B were tested in the catalytic power of the resulting materials. The decolorization process was affected by the dye structure, amount of H2O2, dye concentration, time of reaction, and temperature of the bath. The activation energy values for Allium-CuO were 18.44 kJ mol−1 for calmagite, and 23.28 kJ mol−1 for naphthol blue black, respectively. Nevertheless, the energy values for Allium-AgO were 50.01 kJ mol−1 for calmagite and 12.44 kJ mol−1 for Naphthol blue black. The calculated low energy values for the prepared materials suggested the high efficiency of the use of these catalysts in azo dye decolorization under the change of some main experimental conditions.Chondrilla juncea was employed as a biological extract for in-situ reduction of copper and silver ions within Allium sativum peels. The resulting Allium sativum-CuO and Allium sativum -AgO materials were used as efficient catalysts for azo dye decolorization. [ABSTRACT FROM AUTHOR]

In this research various pyridazino[1,2‐a]indazole and 1H‐indazolo[1,2‐b]phthalazine and 1H‐indazolo[1,2‐b]phthalazine derivatives were produced with a high yield via a multi‐component reaction of dimedone, aldehyde, hydrazine and anhydride compounds in the presence of a novel DABCO‐Saccharin acetate ([DABCOH][Sac‐CH3CO2]) ionic liquid under microwave irradiation. The applied method for producing these heterocyclic compounds demonstrated a number of desirable traits, including quick reactions, high yields of the final product, and straightforward separation of the product and catalyst from the reaction mixture. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis and characterization of novel thiosemicarbazone derivatives with potential antibacterial activity. Through a systematic two‐step synthesis process, involving the preparation of substitute aldehydes (A1–A6) followed by the formation of thiosemicarbazone derivatives (S1–S6), novel compounds (S1, S2) were successfully obtained. The structures of the synthesized compounds were thoroughly characterized using FT‐IR, 1H‐NMR, 13C‐NMR, LC/MS, UV‐Vis, and SEM‐EDX. The results highlight the significance of sulfuric acid as a catalyst in the synthesis of pyrazole‐thiosemicarbazide derivatives (S1, S2), demonstrating its superior efficiency compared to acetic acid. The compounds exhibited varying degrees of antibacterial activity against E. coli, with compounds S3–S6 showing promising results with MIC values below 25 mg/mL. These findings indicate the potential of these compounds as antibacterial agents. Overall, the successful synthesis and characterization of these novel derivatives open avenues for further research into their potential pharmacological applications. The findings of this study lay the foundation for future studies aimed at optimizing these compounds for enhanced antimicrobial activity and exploring their therapeutic potential in treating bacterial infections. [ABSTRACT FROM AUTHOR]

Compared to H2-assisted activation mode, the direct dissociation of CO2 into carbonyl (*CO) with a simplified reaction route is advantageous for CO2-related synthetic processes and catalyst upgrading, while the stable C = O double bond makes it very challenging. Herein, we construct a subnano MoO3 layer on the surface of Mo2N, which provides a dynamically changing surface of MoO3↔MoOx (x < 3) for catalyzing CO2 hydrogenation. Rich oxygen vacancies on the subnano MoOx surface with a high electron donating capacity served as a scissor to directly shear the C = O double bond of CO2 to form CO at a high rate. The O atoms leached in CO2 dissociation are removed timely by H2 to regenerate active oxygen vacancies. Owing to the greatly enhanced dissociative activation of CO2, this MoOx/Mo2N catalyst without any supported active metals shows excellent performance for catalyzing CO2 hydrogenation to CO. The construction of highly disordered defective surface on heterostructures paves a new pathway for molecule activation. The direct dissociation of CO2 into carbonyl (*CO) via a simplified reaction pathway benefits CO2-related synthesis and catalyst improvement, though the stability of the C = O double bond poses a significant challenge. Here, the authors design a subnano MoO3 layer on the surface of Mo2N, offering a dynamically adaptive surface for catalyzing CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Developing sustainable and efficient catalysts for ammonia synthesis from atmospheric molecular N2 under ambient conditions presents a significant 21st‐century challenge. Two‐dimensional heterostructures, particularly single‐atom catalysts (SACs) supported on two‐dimensional materials, have emerged as a promising avenue due to their remarkable catalytic activity and selectivity. Electrides, characterized by an abundance of free electrons and high surface activity, have attracted substantial attention in this context. Through density functional theory (DFT) calculations, this study proposes electride‐graphene heterostructures (EGHS) as catalysts to effectively regulate charge distribution at the catalytic center, facilitating the optimization of catalytic performance. The EGHS model addresses challenges related to excessive adsorbate binding, mitigating electron transfer compared to electride monolayer adsorption. This novel approach utilizes heterogeneous heterostructures to finely tune the catalytic site, optimizing electron input for enhanced catalysis. Based on the optimized charge transfer for N2 activation, the Cr‐doped EGHS (Cr@EGHS) exhibits a promising performance in the nitrogen reduction reaction, leading to, a relatively low limiting potential of −0.85 V and high selectivity. The hypothesis charge transfer depend on N2 activation is further supported by modulating the distance between component layers of heterostructure. These findings contribute to design principles for 2D heterostructure catalysts and offer a reference for experimental synthesis. [ABSTRACT FROM AUTHOR]

In this study, we present a novel method for synthesising zinc oxide nanoparticles (ZnO NPs) from the dried Caesalpinia sappan seeds powder. Comprehensive characterisation using XRD, FTIR, SEM, and EDX techniques was employed to elucidate the surface and morphological properties of these ZnO NPs. We showcase the versatile application of ZnO NPs as heterogeneous catalyst in the synthesis of 5-arylmethylidene-pyrimidin-2,4,6-triones. Notably, this eco-friendly approach eliminates the need for organic solvents, offering a sustainable route to producing 5-arylmethylidene-pyrimidin-2,4,6-triones in high yields. Furthermore, we investigate the corrosion inhibition properties of ZnO NPs on mild steel in 5% sodium chloride solution. Our findings reveal the ZnO NPs’ significant inhibition efficiency against corrosion, promising potential for practical applications. In addition to their chemical applications, we delve into the biological activities of ZnO NPs, including their antibacterial effects against both Gram-positive and Gram-negative bacteria, anti-oncogenic activity against DU-145 cells, and scavenging activities against oxidative stress. [ABSTRACT FROM AUTHOR]

Reported herein is the first viable copper-free bimetallic catalyst for one pot multicomponent synthesis of 1,4-disubstituted 1,2,3-triazoles. A simple thermal procedure followed by two separate solution-phase synthesis methods have been designed to develop a series of Ag-based NPs (namely Ag and Ag2O) supported on the nanorod architecture of ZnO. Utilizing the as-synthesized NPs as the catalyst, we present the first one-step synthesis of 1,4-disubstituted 1,2,3-triazoles at room temperature, in which both benzyl bromides and aryl amines afford their respective benzyl azides and phenyl azides in situ under mild reaction conditions. The catalytic role of the as-synthesized nanoheterostructures was compared with their individual counterparts, revealing that the distinct structural features and oxidation state of Ag in Ag–ZnO and Ag2O–ZnO NPs play a crucial role in the unprecedented catalytic behaviour. Among all, Ag2O–ZnO emerges as the dominant catalyst for the regioselective AAC reaction. Our catalytic protocol eliminates the usage of any external additives, harsh reaction conditions and time-consuming catalyst synthesis. High recoverability of the catalyst (for at least eight catalytic cycles) made the process more useful. The 100% regioselectivity is strongly validated by a single crystal X-ray structure of one of the desired products. It also covers a broad substrate range with extensibility to some medicinally important drug molecules. Because of its gram-level scalability, the protocol can also be designed for industrial use. [ABSTRACT FROM AUTHOR]

Electrocatalytic valorization of glycerol to formate is considered to be a promising sustainable approach; however, it holds great challenges to increase catalyst activity and deliver market‐demanded chemicals with high Faradaic efficiency (FE) and selectivity under industrial‐level current density. Herein, hierarchically structured phosphorus vacancy‐enriched nickel phosphide porous nanoarrays by copper doping, denoted as CuNiP/CuOx‐VP, are constructed via a facile glycol‐mediated solvothermal approach. The CuNiP/CuOx‐VP yields an industry‐level 1 A cm−2 at the ultralow potential of 1.75 V, while showing notable FE (96.94%) and selectivity (96.76%) to formate over a wide range of potentials. Impressively, a two‐electrode electrolyzer linked to H2 evolution possesses exceptional activity that merely requires a cell voltage of 1.45 V to deliver 40 mA cm−2, exhibiting a high FE (97.53%) for formate production and surpassing the vast majority of previously reported precious metal electrocatalysts. Microscopic and electrochemical characterizations manifest that the CuNiP/CuOx‐VP composed of porous NiP nanosheets attached to aggregated CuOx particles featuring superaerophobic‐hydrophilic morphology enables increased active sites, favorable electronic redistribution, and thus boosted electrocatalytic performance. This study demonstrates an effective nanoarrays electrode for catalyst discovery, going from facile catalyst synthesis to structure‐activity relationship and subsequently developing more highly active electrocatalysts for energy‐saving coproduction of valuable chemicals. [ABSTRACT FROM AUTHOR]

Rationally designing distinct acidic and basic sites can greatly enhance performance and deepen our understanding of reaction mechanisms. In our current investigation, we studied the utilization of Brønsted acid sites within layered graphitic carbon nitride (g-C3N4) for the first time to enhance the rate of the Friedländer synthesis. The structural and surface analyses confirm the effective integration of -COOH and -SO3H groups into the g-C3N4 lattice. The surface-functionalized g-C3N4-CO-(CH2)3-SO3H exhibits a remarkable acceleration in quinoline formation, surpassing previously mentioned catalysts, and demonstrating notable recyclability under optimized mild reaction conditions. The heightened reaction rate observed over g-C3N4-CO-(CH2)3-SO3H is attributed to its elevated surface acidity. By probing the Friedländer reaction mechanism through surface characterization, examination of reaction intermediates, and investigation of substrate scope, we elucidate the pivotal role of Brønsted acid sites. This study constitutes a comprehensive exploration of metal-free heterogeneous catalysts for the Friedländer reaction, offering a unique contribution to the field. [ABSTRACT FROM AUTHOR]

In this work, ruthenium-based catalysts were synthesized via polyol reduction method with different metal oxides as support and caesium as promoter. The samples were characterized through XRD, ICP-OES, nitrogen physisorption and XPS. Then, the catalysts were tested for ammonia synthesis in the range of temperatures 548–673 K and pressures 1–5 MPa. The synthesized catalysts allowed an ammonia production rate approximately four times higher compared with the performances of similar catalytic formulations in literature (tested at same conditions). The best performance were achieved with the Cs–Ru/CeO 2 (1% wt Cs, 5% wt Ru), reaching an ammonia production of nearly 73 mmol h−1∙g cat −1 at 673 K and 5 MPa. As showed by the XPS analysis, the increased Ce3+/Ce4+ ratio led to an enhancement of oxygen vacancies, which favoured the dissociative adsorption of nitrogen, that is the limiting step in the ammonia synthesis reaction. Such high catalytic activity can be ascribed to the beneficial effect of the polyol reduction method for the maximization of the exposure of active sites. [Display omitted] • Ru-catalysts were synthesized via polyol reduction and tested for NH 3 production. • Cs–Ru/CeO 2 enabled a NH 3 production rate of 43 mmol h−1∙g cat −1 at 673 K and 1 MPa. • Increased Ce3+/Ce4+ ratio enhanced oxygen vacancies favouring N 2 adsorption. [ABSTRACT FROM AUTHOR]

Rationally designing distinct acidic and basic sites can greatly enhance performance and deepen our understanding of reaction mechanisms. In our current investigation, we studied the utilization of Brønsted acid sites within layered graphitic carbon nitride (g-C3N4) for the first time to enhance the rate of the Friedländer synthesis. The structural and surface analyses confirm the effective integration of -COOH and -SO3H groups into the g-C3N4 lattice. The surface-functionalized g-C3N4-CO-(CH2)3-SO3H exhibits a remarkable acceleration in quinoline formation, surpassing previously mentioned catalysts, and demonstrating notable recyclability under optimized mild reaction conditions. The heightened reaction rate observed over g-C3N4-CO-(CH2)3-SO3H is attributed to its elevated surface acidity. By probing the Friedländer reaction mechanism through surface characterization, examination of reaction intermediates, and investigation of substrate scope, we elucidate the pivotal role of Brønsted acid sites. This study constitutes a comprehensive exploration of metal-free heterogeneous catalysts for the Friedländer reaction, offering a unique contribution to the field. [ABSTRACT FROM AUTHOR]

Graphene, a two‐dimensional material, presents unprecedented opportunities for catalytic applications, attributable to its unique planar structure, outstanding optical transmittance, superior electronic conductivity and mobility, extensive specific surface area, and elevated chemical stability, coupled with its tunability. In recent years, graphene‐based catalysts have garnered significant research attention and interest. This review aims to elucidate recent advancements in the synthesis of graphene‐based catalysts. It encompasses discussions on heteroatom‐doped metal‐free graphene catalysts, graphene composite catalysts (including graphene/metal and graphene/metal oxide composites), and their applications in various catalytic domains such as electrocatalysis, photocatalysis, and catalysis of organic reactions. [ABSTRACT FROM AUTHOR]

Two novel rare earth-substituted tungstoantimonates [H2N(CH3)2]8Na12[Dy2(H2O)6(tar)(Sb2W21O72)]2·40H2O (DySbW) and [H2N(CH3)2]6Na14[Ho2(H2O)6(tar)(Sb2W21O72)]2·25H2O (HoSbW) (H4tar = tartaric acid) were synthesized. The meso-polyanions are alternately linked by {Na3(H2O)3} clusters and DL-tar ligands to form 1D chains. Notably, HoSbW exhibits excellent catalytic activity and high stability for the synthesis of isoindolinones using EtOH as a green solvent. [ABSTRACT FROM AUTHOR]

There is an increasing demand for the development of catalytic reagents that are nontoxic due to the growing environmental concerns in the present organic transformation. Bismuth(III) compounds have significant potential as catalysts for a range of organic synthesis due to their low toxicity, strong Lewis acid catalytic activity, and great flexibility. In this research work, a series of various chemically and pharmacologically important six‐membered fused nitrogen‐/oxygen‐based heterocycle derivatives were efficiently prepared via a one‐pot multicomponent reaction starting from aromatic aldehydes, malononitrile, and barbituric acid in presence of green and reusable Lewis catalyst bismuth(III) triflate, that is, Bi(OTf)3 in EtOH/H2O (1:1) media. Bi(OTf)3 has the additional benefit of being reusable catalyst, ready availability, eco‐friendliness, and easy to handle to obtain corresponding products in excellent yields (83%–94%). Structure of all synthesized products was characterized on the basis of FT‐IR, 1H‐NMR, 13C‐NMR, and ESI–MS analysis. [ABSTRACT FROM AUTHOR]

The impact of radial dispersion of both heat and mass on the behavior of cooled fixed‐bed reactors was explored using a two‐dimensional reactor model. This study accounted for dispersion through an effective radial thermal conductivity (λrad) and a radial dispersion coefficient of mass (Drad), with Fischer–Tropsch synthesis serving as an illustrative process example. Under moderate reaction conditions and hence still rather gentle radial temperature profiles, the effect of mass dispersion on reactor performance was found to be minimal, even if disregarded (Drad = 0), whereas dispersion of heat (λrad) always significantly impacts reactor behavior. Nevertheless, for precise thermal runaway predictions by a reactor model, incorporating mass dispersion by a realistic Drad value is essential. [ABSTRACT FROM AUTHOR]

Among the alkali metals, potassium is known to significantly shift selectivity toward value-added, heavier alkanes and olefins in iron-based Fischer–Tropsch synthesis catalysts. The aim of the present contribution is to shed light on the mechanism of action of alkaline promoters through a systematic study of the structure–reactivity relationships of a series of Fe oxide FTS catalysts promoted with Group I (Li, Na, K, Cs) alkali elements. Reactivity data are compared to structural data based on in situ, synchrotron-based XRD and XPS, as well as temperature-programmed studies (TPR-H2, TPC-CO, TPD-CO2, and TPD-H). It has been observed that the alkali elements induced higher carburization rates, higher basicities, and lower adsorbed hydrogen coverages. Catalyst stability followed the trend Na-Fe > unpromoted > Li-Fe > K-Fe > Cs-Fe, being consistent with the ability of the alkali (Na) to prevent active site loss by catalyst reoxidation. Potassium was the most active in promoting high α hydrocarbon formation. It is active enough to promote CO dissociative adsorption (and the formation of FeCx active phases) and decrease the surface coverage of H-adsorbed species, but it is not so active as to cause premature catalyst deactivation by the formation of a carbon layer resulting in the blocking active sites. [ABSTRACT FROM AUTHOR]

Objectives: Salophen-type Schiff bases functionalized with 4-(dimethylamino)pyridinium halide units are shown to be effective single-component catalysts for the synthesis of cyclic carbonates from terminal epoxides and carbon dioxide. Methods: Using one of such trifunctional organocatalysts, epichlorohydrin could be selectively converted to the target cyclic carbonate under 2 bar of CO2 at 120 °C. Results: Over 80% conversion of E3 was then observed when organocatalyst S3 was used in the amount of 0.5 mol% (TON = 156) and even the use of 0.05 mol% S3 guaranteed almost 50% conversion of E3 to C3 (TON = 893). Conclusions: The presence of tertiary amine units in the molecules of these homogeneous organocatalysts proved to be crucial for the catalytic activity of developed organocatalysts. However, their catalytic activity was also supported by the presence of acidic phenolic units and halide ions as Lewis bases. Some closely related compounds were found to be clearly less active or inactive catalytically under the applied reaction conditions. [ABSTRACT FROM AUTHOR]

Zirconia nanocrystals as catalysts for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide have received significant interest recently. In this paper, three zirconia-based catalysts presenting different monoclinic and tetragonal phase contents are prepared and characterized by X-ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), and temperature-programmed desorption of NH3 and CO2 (NH3-TPD and CO2-TPD). The catalytic performances of these solids are evaluated in terms of DMC production. This production is low when using the bare zirconias, but it is significantly increased in the presence of 1,1,1-trimethoxymethane (TMM) playing the role of a dehydrating agent, which shifts the thermodynamic equilibrium. Moreover, the production of DMC is further improved by adding a second solid catalyst (cocatalyst), the molecular sieve 13X, to accelerate the hydration of TMM. Hence, the molecular sieve 13X plays a dual role by trapping water molecules formed by the reaction of DMC synthesis and providing strong acidic sites catalyzing TMM hydrolysis. To the best of our knowledge, the combination of two solid catalysts in the reaction medium to accelerate the water elimination to obtain higher DMC production from CO2 and methanol has never been reported. [ABSTRACT FROM AUTHOR]

We used stable and nontoxic [(dimethylamino)methyl]ferrocene (Fc‐N), (hydroxymethyl)ferrocene (Fc‐O), 1,2‐bis[(dimethylamino)methyl]ferrocene (Fc‐N2), and 1‐[(dimethylamino)methyl]‐2‐(hydroxymethyl)ferrocene (Fc‐NO) as halide‐free, neutral, and bifunctional one‐component catalysts for the synthesis of cyclic carbonates. They do not need halide‐based additives or tethered salts attached to ligands when used for this coupling reaction. Among them, Fc‐N2 exhibited the best catalytic activity under the same reaction conditions. Catalytic activity decreased rapidly in the order Fc‐N2 > Fc‐NO > Fc‐N > Fc‐O, and interestingly, the more amino groups introduced into the Cp groups, the higher the activity. Various terminal and internal epoxides were easily converted into the corresponding cyclic carbonates. Calculations based on the density functional theory were also carried out to elucidate the mechanism of the coupling reaction. [ABSTRACT FROM AUTHOR]

In sustainable agricultural production, an efficient and environmentally-friendly nano-drug carrier system is a considerably efficient way to enhance the efficacy of pesticides and minimize ecological side effects. In this study, tetraethyl orthosilicate (TEOS) was used as the silicon source with ammonia as the catalyst for the synthesis of hollow mesoporous silica (HMS) by a self-template method. HMS was loaded with emamectin benzoate (EB) by co-solvent method to prepare nano-drug carrier system (HMS-EB). Chitosan (CS) was covalently modified on the surface of HMS-EB to obtain a good foliage adhesion nano-drug carrier system (CS@HMS-EB). Results showed that the prepared CS@HMS-EB had a regular spherical shape and uniform particle size, with an average particle size of about 200 nm and a drug loading rate of 45.3%. Through the covalent interaction, CS successfully adhered to the surface of HMS-EB, which significantly improved the wetting, adhesion and retention capacity of EB on the surface of maize leaves. Moreover, under UV-light irradiation, the degradation rate of EB loaded in the CS@HMS-EB decreased by 40% compared with EB alone. Meanwhile, CS@HMS-EB had a good sustained release property. Importantly, Both indoor and field bioactivity evaluation assays showed that compared with commercial 5% emamectin benzoate microemulsion (EB ME), CS@HMS-EB exhibited higher insecticidal activity against Spodoptera furgiperda larvae. This nano-drug carrier system does not contain organic solvents and has good insecticidal activity, which is expecting to play a broad application prospect in pest control. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and utilization (ICCU) simplifies the CO2 utilization process by converting chemically combined CO2 molecules into value-added chemicals, leading to a strong energy-saving effect by omitting the CO2 separation process. Two reaction routes for the hydrogenation of amine captured CO2 to methanol over heterogeneous catalysts were summarized: alcoholic hydroxyl groups-promoted CO2 hydrogenation process over Cu or Pd-based catalysts via formate and ester route, and methanol production from the direct hydrogenation of formate over Au-based catalyst. The technical effectiveness of concurrent carbon capture with heterogeneous catalysis toward methanol via alcoholic hydroxyl groups-promoted CO2 hydrogenation is similar to that of the gas-phase CO2 hydrogenation to methanol over heterogeneous catalysts. The sintering of the catalysts, the phase change of the supports, the combination of amines and the catalysts (namely leaching), and the reaction of water with the supports can cause a decrease in the performance of the catalysts. Thus, it is important to rationally design next-generation stable catalysts to achieve amine captured CO2 hydrogenation to methanol while at the same time regenerating amines. The development of heterogeneous catalysts for methanol synthesis in the liquid phase and the development of the CO2 capture process for subsequent conversion(1 ~ 70%) were carefully reviewed. The integration and optimization of multi-pollutant efficient removal technology, selectively coupled CO2 capture technology, and selective routes for methanol synthesis can achieve industrial verification in typical power plants, which is of great significance in promoting energy conservation, emission reduction, and low-carbon footprint. [ABSTRACT FROM AUTHOR]

Chiral pincer complexes, characterized by their rigid tridentate coordination framework, have emerged as powerful catalysts in asymmetric synthesis. This review provides a comprehensive overview of recent advancements in the development of chiral pincer-type ligands and their corresponding transition metal complexes. We highlight the latest progress in their application across a range of catalytic asymmetric reactions, including the (transfer) hydrogenation of polar and non-polar bonds, hydrophosphination, alkynylation, Friedel-Crafts reactions, enantioselective reductive cyclization of alkynyl-tethered cyclohexadienones, enantioselective hydrosilylation, as well as Aza–Morita–Baylis–Hillman reactions. The structural rigidity and tunability of chiral pincer complexes enable precise control over stereoselectivity, resulting in high enantioselectivity and efficiency in complex molecular transformations. As the field advances, innovations in ligand design and the exploration of new metal centers are expected to expand the scope and utility of these catalysts, bearing significant implications for the synthesis of enantioenriched compounds in pharmaceuticals, materials science, and beyond. [ABSTRACT FROM AUTHOR]

This study investigated the dynamic structure of a working Cu/CeO2 catalyst and its catalytic consequences for CH3OH synthesis via CO hydrogenation by kinetics, high‐precise chemical titration, and a series of in situ X‐ray spectroscopies. We have revealed that the apparent rate coefficients for CH3OH synthesis from CO hydrogenation are a single‐valued function of the CO2‐to‐CO ratio in the contacting gas phase. This ratio determines the extent of surface oxidation of Ce2O3 to CeO2, the relative abundance of surface Ce3+ and Ce4+ sites, and in turn, the density of Cu0‐Ce3+ sites pair on the working Cu/CeO2 catalyst, although the chemical state of Cu and elemental distribution of both Cu and Ce were insensitive to the ratio. The reactivity of CH3OH formation and the Cu0‐Ce3+ sites decrease monotonously with an increase in the CO2‐to‐CO ratio. The direct connection of the reactivity and the oxidant‐to‐reductant ratio appears to be general for heterogeneous catalysis, for which the oxidant oxidizes metal atoms. In contrast, the reductant scavenges surface oxygen atoms, thus dictating the density of surface sites and their thermodynamic activities. [ABSTRACT FROM AUTHOR]

The high selectivity of C─C coupling reactions in Fischer–Tropsch synthesis (FTS) is often limited due to the difficulty in the regulation of transition metals acting as active sites to balance between C─C chain propagation and over hydrogenation. Herein, BCN‐supported CoFe alloy catalyst has been successfully constructed for promoting C─C chain propagation. When exposed to light irradiation, the CoFe‐BCN catalyst exhibits a higher CO conversion of 18.4% with the enhanced selectivity toward multi‐carbon (C2+) hydrocarbons that increases from 22.4% to 64.1%, and the reduced over hydrogenation to CH4 that decreases from 74.8% to 25.4% in contrast to Co‐BCN catalyst. Structural characterizations indicate that introducing Fe to create CoFe alloy can decrease the d‐band center of Co, which significantly promotes C─C coupling reactions but weakens hydrogenation in FTS process. The findings underscore the potential of modifying catalysts with metal atoms to optimize their electronic structure to regulate reaction pathways in CO hydrogenation for high‐value products formation. [ABSTRACT FROM AUTHOR]

Fischer-Tropsch synthesis (FTS) converts syngas into multi-carbon products, whose distribution is highly dependent on the catalyst structure. Here, nano-iron catalysts with different silica supports were prepared, and their activities and durability for Fischer-Tropsch to olefins (FTO) process were investigated. Fe/KCC-1 demonstrated the best FTO catalytic selectivity of 25.0% for C2–4= and an olefin-to-paraffin ratio of 1.68. Its open pore structure allowed primary olefins to escape quickly from the catalyst surface, lowering the probability for secondary reactions. However, its durability was lower than Fe/SBA-15 due to coke formation, pore structure collapse and Fe particle agglomeration. The thermal stability of SBA-15 resulted in its better durability, and the encapsulated Fe particles inside the cylindrical mesopores also allowed better resistance to sintering. However, the less open structure of Fe/SBA-15 led to longer residence time for the primary olefins and increased possibility for secondary reactions, causing undesired chain growth. [ABSTRACT FROM AUTHOR]