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The acetylation of proteins' N-terminal amino groups by the N-acetyltransferase complexes plays a crucial role in modulating the spatial stability and functional activities of diverse human proteins. Mutations disrupting the stability and function of NAA10 result in X-linked rare genetic disorders. In this study, we conducted a global analysis of the impact of fifteen disease-associated missense mutations in NAA10. The analyses revealed that mutations in specific residues, such as Y43, V107, V111, and F128, predictably disrupted interactions essential for NAA10 stability, while most mutations (except R79C, A111W, Q129P, and N178K) expectedly led to structural destabilization. Mutations in many conserved residues within short linear motifs and post-translational modification sites were predicted to affect NAA10 functionality and regulation. All mutations were classified as pathogenic, with F128I and F128L identified as the most destabilizing mutations. The findings show that the F128L and F128I mutations employ different mechanisms for the loss of catalytic activities of NAA10F128L and NAA10F128I due to their structural instability. These two mutations induce distinct folding energy states that differentially modulate the structures of different regions of NAA10F128L and NAA10F128I. Specifically, the predicted instability caused by the F128I mutation results in decreased flexibility within the substrate-binding region, impairing the substrate peptide binding ability of NAA10F128I. Conversely, F128L is predicted to reduce the flexibility of the region containing the acetyl-CoA binding residues in NAA10F128L. Our study provides insights into the mechanism of catalytic inactivation of mutants of NAA10, particularly elucidating the mechanistic features of the structural and functional pathogenicity of the F128L and F128I mutations.

Effluents of the dying and printing industries are a significant contributor to water pollution. Since synthetic dyes are primarily resistant to natural degradation, they remain in water bodies for an exceptionally long time if discharged untreated. Oxygen dark activation is a promising candidate for the degradation of azo dyes as it does not require the use of additional reagents or even the presence of light. It is an advanced catalytic oxidation process that converts oxygen dissolved in wastewater into reactive oxygen species, which subsequently break down dye molecules. The role of the catalyst is to accelerate the process by acting as a bridge for the electron transfer between the dye molecules and adsorbed oxygen. It has been reported that the textural and structural properties of the catalyst play a key role in generating reactive oxygen species. In this work, we synthesized, characterized, and evaluated a series of strontium-based perovskite oxides for the catalytic degradation of azo dyes under dark conditions. The degradation of different dyes was studied in a batch reactor under various conditions, and the reaction progress was monitored by UV–vis absorption spectroscopy. The results showed that the degradation of azo dye was faster when the azo bond was weakened by either electron-withdrawing groups or due to the formation of a stable hydrazone structure. To evaluate the effect of structural defects on the oxygen dark activation process, cation non-stoichiometry was separately introduced in the parent perovskite SrFeO3 at both A and B sites. Under identical reaction conditions, the degradation efficiency of A-site deficient perovskite Sr0.90FeO3 (94 %) and B-site deficient SrFe0.80O3 (95 %) was higher than the stoichiometric perovskite SrFeO3 (46 %). These results demonstrate that cation deficiency in the SrFeO3 structure strongly favors the catalytic degradation of azo dyes via oxygen dark activation.

Nanofluids consisting of tetra nanoparticles are crucial in bio medical sciences due to their improved thermal transport characteristics. The advanced tailored properties of tera nanoparticles make them useful in several medical interventions, such as hyperthermia treatment, where the targeted tissue can be heated more efficiently, leading to better treatment outcomes. The current study investigates the heat transfer enhancement in a hemodynamic system using tetra nanoparticles. The physical configuration of the blood flow is assumed with in a permeable cylindrical shape stenosed artery. The model incorporates the Carreau model with inclusion of diverse factors such as, exponential space-based heat source, viscous dissipation, infinite shear rate and permeability of surface. Additionally, impact of chemical reaction (autocatalysis) and magnetohydrodynamic (MHD) consequences is also integrated into the system. The framed partial differential equations (PDEs) generated by physical problem are converted into new dimensionless form of an ordinary differential system (ODEs). Bvp4c MATLAB procedure is fetched for numerical investigation. It is observed that, velocity profile of the fluid is reduced due to intensification in inclined magnetic effect, whereas autocatalysis effect promotes the concentration of nanoparticles in blood flow mixture, which increases the temperature field of fluid. Furthermore, augmentation in the values of Wassenberg number increased the elasticity in blood which enables it to deform and stretch more readily in reaction to alterations in flow conditions and hence reduction is seen in overall blood flow rate. The results revealed the significance of these integrated factors for accurate modelling of blood flow passing through a stenosed artery, which is crucial in medical interventions.

Investigating the kinetics of polymerization reactions is a powerful tool to obtain information for the engineering design of such processes. It provides insights into how the relative rates of elementary reactions which influence both the kinetics of the reactions and thus characteristics of the products as well, particularly when the reaction parameters of these reactions are unknown. Among polymerization processes, ring-opening metathesis polymerization (ROMP) has gained broad academic and industrial interest, due to its mild conditions to obtain a wide range of polymer products. In this study, kinetic Monte Carlo simulation was applied to reveal the effect of the elementary reactions of ROMP on the kinetics and product distribution. Both the propagation and the cross-metathesis reactions were considered, with the latter leading to the formation of various types of macrospecies whose population levels were also monitored. Relevant tendencies were observed regarding how the variations in the reaction parameters of the elementary reactions of this polymerization process, such as reaction probabilities, monomer addition method, catalyst-to-monomer ratio, and reaction time, affect the kinetics of the polymerization process and the product distributions. These variations also influence the key macromolecular parameters of the resulting polymeric materials, including chain length distribution (CLD), population levels, and polymer functionalities. The results of this study indicate that this simulation technique is a valuable tool for mapping the tailoring possibilities of modifying the reaction parameters of ROMP to achieve desired properties. These properties include number average molecular weight, polydispersity, chain end functionality, and macrocycle-free products.

Bismuth based MOFs have appealed much curiosity in different catalytic processes due to their remarkable properties, which include their porous structure, less toxicity, abundance and high specific surface area. With their distributed active sites and constrained reaction regions, Bi based MOFs have a bright future as catalysts for extremely focused CO2 reduction by electrocatalysis reactions (ECO2RR). Formic acid (HCOOH), one of the byproducts of these processes, is notable because of its high economic worth. An extensive summary of Bi-MOFs and their derivatives used in ECO2RR and the photocatalytic reduction of CO2 into useful compounds is given in this review. Bi-MOFs synthesis methods for both electro and photocatalyst applications are discussed, along with an analysis of their unique benefits. Interestingly, a variety of Bi-MOFs and related offshoots are highlighted, including bimetallic catalysts and Bi-based MOF-derived nanocomposites. Bi-MOFs catalysts’ catalytic efficacy is demonstrated to be closely related to the MOF structure blocks-metal ions and organic linkers as well as particular circumstances controlling their derivatization. As a result, Bi-MOFs catalysts have a wide range of functions and provide the possibility of controlling the catalytic performance. This review describes the current obstacles in this area and makes recommendations for future research paths to advance the use of Bi-MOFs as electro- and photocatalysts.

Summary: Gold(I)-catalyzed highly enantioselective [4 + 2] cycloadditions of 1,6-enynes were achieved by utilizing chiral bifunctional P,N ligand. A wide range of 1,6-enynes were converted to enantioenriched 5-6-6-fused tricyclic compounds under mild reaction condition (up to 99% ee). This chiral gold(I) complex was also employed in the first desymmetric cycloadditions of 1,6-diynes bearing single ester group at the tether (up to 93% ee), where 5-exo-dig pathway predominates over 6-endo-dig pathway. DFT calculations and control experiments were performed to rationalize the origin of precise stereocontrol. It implies that hydrogen bonding interaction between the ester group of substrates and the secondary amine of the chiral P,N ligands plays a pivotal role in the control of enantioselectivity. The utilities of the current reaction were demonstrated by scale-up experiment and derivatizations.

Summary: The photocatalytic reduction of carbon dioxide (CO2) into multi-electron carbon products remains challenging due to the inherent stability of CO2 and slow multi-electron transfer kinetics. Here in, we synthesized a hybrid material, cesium copper halide (Cs3Cu2I5) intercalated onto two-dimensional (2D) cobalt-based zeolite framework (ZIF-9-III) nanosheets (denoted as Cs3Cu2I5@ZIF-1) through a simple mechanochemical grinding. The synergy in the hybrid effectively reduces CO2 to carbon monoxide (CO) at 110 μmol/g/h and methane at 5 μmol/g/h with high selectivity, suppressing hydrogen evolution. Further, we have investigated additional Cs3Cu2I5@ZIF hybrids with varying ZIF-9-III amounts, confirming their selective CO2 reduction to methane over hydrogen. Density functional theory (DFT) calculations reveal a non-covalent interaction between Cs3Cu2I5 and ZIF-9-III, with electron transfer suggesting potential for improved photocatalysis.

Summary: Exploration of efficient Ru-based catalysts is significant for advancing the production of hydrogen from ammonia decomposition, which depends predominantly on the rational regulation of the metal-support interaction of Ru-based catalysts. Herein, highly dispersed Ru nanoparticles (NPs) on Gd2O3 (Ru/Gd2O3) are developed and applied for the NH3 decomposition reaction. By varying the reduction temperature, the activity of the Ru/Gd2O3 catalyst can be remarkably improved. Characterization results reveal that the enhanced activity is associated with the strong metal‒support interaction (SMSI) induced formation of Gd2O3 overlayer on the Ru NPs. With a relatively low reduction temperature, the exposed Ru NPs possess relatively low activity toward NH3 decomposition. After high temperature activation treatment, the Gd2O3 overlayer coated Ru NPs show much enhanced intrinsic activity than that of the exposed Ru NPs. This study brings a facile strategy to modulate the catalytic performance of oxide supported Ru catalysts by regulating the SMSI of catalysts.

The extraction, processing, and utilization of petroleum often results in the release of diverse hydrocarbon pollutants into the environment, leading to severe ecological and health implications. Herein, the adsorption and separation of ethane (EAN), ethene (EEN), ethyne (EYN), and benzene (BZN) fractions of paraffin, olefin, acetylene, and aromatic petroleum hydrocarbons were investigated via the catalytically engineered nickel group transition metals; nickel (Ni), palladium (Pd), and platinum (Pt). These transition metals were coordinated on Germanium-doped graphitic carbon nitride (Ge@g-C3N4) nanostructures, and the behavior of the systems was studied through Kohn–Sham density functional theory (KS-DFT) with the B3LYP–D3(BJ)/Def2-SVP computational method. The adsorption of petroleum hydrocarbons decreased in the order Ge_Ni@C3N4 > Ge_Pd@C3N4 > Ge_Pt@C3N4>Ge_Pt@C3N4. These results showed that the coordination of Ni, Pd, and Pt within Ge@C3N4 improved the separation of petroleum hydrocarbons.

The stability of metal nanoclusters (NCs) on graphene supports is crucial for their applications in catalysis. Here, we report on the preparation of a composite material comprising Au NCs on graphene support with multi-curvature defects through the vapor deposition of porous Au and in situ heating, followed by a preliminary exploration of its structural stability. Transmission electron microscopy revealed dense encapsulation of Au NCs within the spatial folds of the graphene support, with their structure and position remaining stable over 1 min at 800 °C, indicating exceptional structural stability. X-ray photoelectron spectroscopy (XPS) characterization and density-functional theory (DFT) calculations demonstrate that this stabilizing effect is attributed to the unique electronic properties of the graphene surface, particularly its spatial curvature and topology with defects. Graphene surfaces with multi-curvature defects exhibit a stronger anchoring effect toward Au NCs compared to planar graphene. This work provides a theoretical basis for advancing the design and optimization of graphene-supported metal cluster catalysts.

Summary: The varied pigments found in animals play both ecological and physiological roles. Virtually all echinoderms contain putative pigment biosynthetic enzymes, the polyketide synthases (PKSs). Among these, crinoids have complex pigments found both today and in ancient fossils. Here, we characterize a key pigment biosynthetic enzyme, CrPKS from the crinoid Anneissia japonica. We show that CrPKS produces 14-carbon aromatic pigment precursors. Despite making a compound previously found in fungi, the crinoid enzyme operates by different biochemical principles, helping to explain the diverse animal PKSs found throughout the metazoan (animal) kingdom. Unlike SpPks1 from sea urchins that had strict starter unit selectivity, CrPKS also incorporated starter units butyryl- or ethylmalonyl-CoA to synthesize a crinoid pigment precursor with a saturated side chain. By performing biochemical experiments, we show how changes in the echinoderm pigment biosynthetic enzymes unveil the vast variety of colors found in animals today.

Summary: The development of efficient catalysts for ammonia synthesis under mild conditions is critical for establishing a carbon-neutral society powered by renewable ammonia. While significant effort has been focused on Fe and Ru-based catalysts, there have been very limited studies on manganese-based catalysts for ammonia synthesis because of their low intrinsic catalytic activity. Herein, we report that the synergy between manganese nitride (Mn4N) and europium nitride (EuN) yields an ammonia synthesis rate that is 41 and 25 times higher than that of neat Mn4N and EuN, respectively. Detailed studies suggest that a [Eu-N-Mn] species at the interface of Mn4N and EuN plays a pivotal role in ammonia synthesis. Compositing of Mn4N with other rare earth metal nitrides such as LaN, PrN, and CeN also leads to a significant enhancement in catalytic activity. This work broadens the scope of advanced nitride catalysts for ammonia synthesis.

Summary: A crucial challenge in hydrogen production through electrolysis is developing inexpensive, earth-abundant, and highly efficient Pt-free electrocatalysts for the hydrogen evolution reaction (HER). Molybdenum carbide is ideal for this application because of its special electrical structure, low cost, and advantageous characteristics. Herein, the long-lived electrocatalysts for HER have been synthesized via the direct current (DC) arc discharge plasma method under ambient air conditions, and the relationship between the properties of materials and catalytic characteristics has been established. The samples differed in the ratio of molybdenum, graphite, and melamine. The sample with the highest proportion of melamine in the initial mixture has Mo2C-MoO2 heterointerfaces, which demonstrates the highest and most stable electrocatalytic activity with the overpotential of 148 mV at 10 mA·cm-2 and Tafel slope of 63 mV·dec−1 in alkaline electrolyte. Meanwhile, the electrodes demonstrated long-lived electrochemical durability for two weeks and investigated the features of forming a stable system for HER.

Summary: ATP-citrate lyase (ACLY) is a critical metabolic enzyme and promising target for drug development. The structure determinations of ACLY have revealed its homotetramer states with various subunit symmetries, but catalytic mechanism of ACLY tetramer and the importance of subunit symmetry have not been clarified. Here, we constructed the free energy landscape of ACLY tetramer with arbitrary subunit symmetries and investigated energetic and conformational coupling of subunits during citryl-CoA synthesis process. The optimal conformational pathway indicates that ACLY tetramer encounters three critical conformational barriers and undergoes a loss of rigid-D2 symmetry to gain an energetic advantage. Energetic coupling of conformational changes and biochemical reactions suggests that these biological events are not independent but rather coupled with each other, showing a comparable energy barrier to the experimental data for the rate-limiting step. These findings could contribute to further research on catalytic mechanism, functional modulation, and inhibitor design of ACLY.

This study is aimed at investigating the effect of tungsten-based catalysts for aerobic oxidative desulfurization (AODS) for gas oil. Two catalysts tungsten loaded on activated carbon (W/AC) and cerium-tungsten load on activated carbon (Ce–W/AC) were prepared, and they are characterized by Fourier transform infrared spectroscopy FTIR, X-ray diffraction (XRD), Scanning electronic microscopy (SEM), Energy dispersive spectroscopy EDX, and thermal behavior was examined by thermal graphometry analysis (TGA), the surface area was measure by Brunauer-Emmett-Teller (BET) method. The experiments were conducted in a lab-scale reactor. The primary investigation shows that Ce–W/AC was more active than W/AC. The second part examines the effect of reaction temperature, air flow rate, and catalyst dosage on sulfur removal efficiency by using Ce–W/AC, the ranges for the studied parameter are 150–200 °C, 20–60 mL/min, and 0.5–1 g for reaction temperature, air flow rate, and catalyst dosage respectively. The experiments were designed according to the Taguchi method. The experiments results show the sulfur removal efficiency ranged between 72.3 and 99.9. The findings demonstrate that increasing the reaction temperature leads to an increase in sulfur removal efficiency, while the increase in sulfur removal efficiency with air flow rate and catalyst dosage did not continue because it started decreasing after it reached a maximum value According to analysis variance ANOVA demonstrated that the effect of the studied variables ordered the following: reaction temperature air flow rate and finally catalyst dosage via their F-value where these values are 12.27, 4.09, and 0.16 for reaction temperature, air flow rate, and catalyst dosage respectively.

The water-gas shift (WGS) reaction is pivotal in industries aiming to convert carbon monoxide, a byproduct of steam reforming of methane and other hydrocarbons, into carbon dioxide and hydrogen. Selecting an effective catalyst for this transformation poses a substantial challenge, as it requires a delicate balance between conversion, stability, and cost. We combine machine learning-driven prediction models with Bayesian optimization to explore and identify novel catalyst compositions. The proposed method efficiently explores the catalysis composition space for a predefined set of active metals, supports, and promoters to identify the most promising catalyst formulations. We assign weights to different performance metrics of catalysts, enabling tailored optimization according to specific industry needs. Our screening system streamlines catalyst discovery and facilitates the screening and selection of catalysts that balance conversion performance, stability, and cost-effectiveness. This approach holds significant promise for advancement in heterogeneous catalysis to meet the growing demands of efficient industrial processes.

The production of hydrogen and syngas (H2/CO) from waste tires by pyrolysis catalytic steam reforming was investigated in a two-stage fixed bed reactor. In this study, tire char served as a sacrificial catalyst, facilitating the combination of catalytic steam reforming and char steam gasification reactions. The tire char acted as both a catalyst and a gasification reactant, enhancing the gas product yield. The process parameters investigated were, a reforming temperature range of 700–1000 °C, steam space velocity between 2 and 12 g h−1 g−1char and reaction times of 0.5–2 h. The influence of the parameters on the yield and composition of the product gases and the characteristics of the used catalyst were analyzed in detail. The results indicated that higher temperature and steam space velocity increased H2 and CO yields in the presence of a tire char catalyst. Elemental analysis of the used tire char, surface morphology and pore structure provided insights into the extent of tire char consumption in the reaction. Prolonged reaction time allowed for more thorough reactions between the pyrolysis volatiles and tire char, promoting the production of H2. At a reaction time of 2 h, the H2 yield reached 223 mmol g−1, representing 74 wt% of the maximum hydrogen yield.

Metal oxides are versatile catalysts in organic synthesis, exhibiting diverse properties such as acidity, basicity, redox behaviour, and stability. Among these, tin dioxide (SnO₂) stands out for its resilience and durability, making it a preferred catalyst. The reduced ionic character and high oxidation state (+4) of tin dioxide contribute to its heightened acidity. Tin dioxide based materials have gained significant attention as catalysts in heterocycle synthesis, cross-coupling, decarboxylation, ring-opening and ring-closing reactions, biodiesel synthesis, and glycerol transformations. Additionally, SnO₂-based materials are also employed as photocatalysts and photo-electrocatalysts.

Metal complexes not only play an essential role in various technologies and industries, but they are also serving with efficiencies in the fields of catalysis, medicine, dye, agrochemicals, polymers, and other important materials for human society. They have been used from antiquity to recent times, with advancements in their synthesis and characterization. Recently, sustainable synthetic techniques like microwave synthesis, sonochemical synthesis, and grinding assisted microwave synthesis have become advanced methods. Sustainable inorganic complex-based materials are also being developed due to their specific properties and mechanisms compared to synthesized organic compound-based materials. Characterization techniques, such as spectroscopic, crystallographic, computational methods, etc., play a pivotal role in elucidating the structural and electronic properties of metal complexes. Inorganic complexes have potential to solve problems like drug resistance in the medicinal field, target drug delivery in cancer therapy, catalysts for pollutants degradation in pollution control, and also for cost effective production of renewable energy. Thus, they are not only efficient materials for the present but also for the future. By examining recent literature, the present review provides a comprehensive summary of innovative green synthetic methodologies, advanced sustainable characterization techniques, and emerging applications in catalysis, materials science, and medicinal chemistry. Additionally, future directions and potential avenues of coordination compounds for further exploration in the dynamic field of coordination chemistry have been discussed.

Summary: Nitrogen doped carbon materials have been studied as catalyst support for ammonia decomposition. There are 4 different types of nitrogen environments (graphitic, pyrrolic, pyridinic and nitrogen oxide) on the amorphous support identified. In this paper, we report a 5%Ru on MgCO3 pre-treated nitrogen doped carbon catalyst with high content of edge nitrogen-containing sites which displays an ammonia conversion rate of over 90% at 500°C and WHSV = 30,000 mL gcat−1 h−1. It also gives an impressive hydrogen production rate of 31.3 mmol/(min gcat) with low apparent activation energy of 43 kJ mol−1. Fundamental studies indicate that the distinct average Ru-N4 coordination site on edge regions is responsible for such high catalytic activity. Ammonia is stepwise decomposed via a Ru-N(H)-N(H)-Ru intermediate. This associative mechanism circumvents the direct cleavage of energetic surface nitrogen from metal to form N2 hence lowering the activation barrier for the decomposition over this catalyst.

Summary: C3N4 is widely applied in the synthesis of single-atom catalysts. However, understanding on the active site and the reaction mechanism is not fully in consensus. Especially, bare studies have considered the coordination environment of the single-atomic dopant and the effect of nitrogen vacancy on C3N4. In this study, we found that the presence of nitrogen vacancies promotes the activation of water and reduces the activation energy barrier for hydrogen generation. The results show that a synergistic effect between single-atom Pt and nitrogen vacancies enables the catalyst to achieve a superior hydrogen production rate of 3,890 μmol/g/h, which is 16.8 times higher than that of pristine C3N4. Moreover, the catalyst is also applicable for photocatalytic hydrogen production from seawater without significantly decreased hydrogen production rate. This study paves the way for the rational design and optimization of next-generation photocatalysts for sustainable energy applications, particularly in solar-driven hydrogen production.

Summary: Pulsed electrolysis has emerged as a promising approach to CO2 reduction, offering a simple method to adjust product selectivity and enhance operational stability. However, conceptually applying the dynamic pulse operation process on a large scale highlights its differences when compared to conventional electrolysis processes, impacting the economic feasibility of the process. We discuss the influence of pulsed electrolysis on surface reaction mechanisms and the simulation of changes at both the continuum and smaller scales through computational modeling. Additionally, we point out considerations for applying pulsed CO2 electrolysis to a large-scale process and assess their economic implications, comparing pulsed electrolysis with constant electrolysis.

Summary: Selecting a suitable photocatalyst to establish the Z-scheme heterojunction which is accompanied by effective photogenerated hole and electron separation, is one of the advantageous strategies for efficient photocatalytic solar energy conversion. Therefore, we prepared a ZnIn2Se4 nanoparticles photocatalyst to build a double Z-scheme heterojunction with mixed-phase TiO2 nanofibers, boosting photocatalytic solar fuel preparation. The result of X-ray photoelectron spectroscopy confirmed the existence of interfacial chemical bonds and internal electric fields. The interfacial Ti-Se bond is regarded as a channel and the internal electric field serves as the driving force for electron transfer. And the composite photocatalyst exhibits a great hydrogen evolution rate of 0.11 mmol g−1 h−1. From a forward-working perspective, this work proposes a ZnIn2Se4 nanoparticles photocatalyst for efficient solar fuel conversion, promoting the application of bimetallic selenide photocatalyst in the field of photocatalysis.

Summary: In this study, the theoretical calculations proves that the combination of oxygen vacancy and amorphous carbon films in TiO2 (VO-CT) can effectively reduce the energy bandgap and work function. The minimum Gibbs free energies required for the CO2RR reaction of VO-CT are 0.20 eV, which is lower than pure TiO2. The amorphous c@TiO2 nanomaterials with oxygen vacancy and mesoporous structures (VO-MCT) are prepared with the P123 surfactant as the template and oxalic acid as an inducer. The electron paramagnetic resonance indicates the presence of abundant oxygen vacancy defects in the samples. UV-vis spectra indicate that the mesoporous structure enhances light absorption capacity. The photocatalytic CO2 reduction tests show that the highest conversion rates for CH4 and CO of VO-MCT are 14 μmol g−1 h−1 and 10.66 μmol g−1 h−1, respectively. The electron consumption rate of VO-MCT is 12.43 times higher than that of commercial TiO2 (P200).

Summary: Direct and stable conversion of CO2 to aromatics (CTA) is an attractive route for reducing CO2 emissions. However, due to the chemical inertness of CO2, direct CTA reaction with high aromatics selectivity is still challenging. In this work, a tandem catalyst Zn0.1Ti0.9Ox/HZSM-5 with appropriate density and strength of acid sites exhibits a high aromatics selectivity of 67.2% and long-term stability over 100 h. Furthermore, the total selectivity of benzene, toluene, and xylene achieves 24.1% over Zn0.1Ti0.9Ox/HZSM-5 with a modified hydrophilic surface. In addition, the CTA via the formate route has been determined in this reaction system.

Summary: The effect on catalytic behavior induced by different morphology of NiO supports has been investigated using the example of gold-catalyzed CO oxidation. Three NiO-supported nanogold consisting of nanogold deposited onto NiO nanorods (NiO-R), nanosheet (NiO-S), and nanodiscs (NiO-D) were prepared. Transmission electron microscopy(TEM)/Scanning transmission electron microscopy(STEM) investigations indicated that Au particles dominantly exposed Au(111) facets virtually independent of NiO architectures. Au/NiO-S displayed a normal Arrhenius-type behavior. Au/NiO-R and Au/NiO-D showed an atypical behavior, characterized by a U-shaped curve of activity vs. temperature, which is attributed to the carbonate accumulation on whose catalytically active sites. On Au/NiO-R, a stable CO-conversion rate of 1.78 molCO gAu−1 h−1 at 30°C was achieved, which is among the higher rates reported so far for supported Au-based systems. DRIFTS measurement identified Auδ+ species as crucial CO adsorption sites promoting CO oxidation, and the catalytic CO oxidation should obey Mars-van Krevelen (240°C).

In this study, Co-based catalysts supported over Ti-Al oxide and promoted with La, Ce, Mg, and K metals were assessed for CO2 reforming of methane reaction to produce syngas. Titania-alumina mixed oxide supports were prepared using the template-assisted-solvothermal method, and then Co and promotors were co-impregnated over the as-prepared support. Different characterizations of catalysts showed that variation in promotor metal impacts these catalysts' physical and chemical properties. The Ti-Al oxide support possessed the perfect hexagonal morphology. Potassium-promoted catalysts possessed the highest number of basic sites, whereas the La-promoted catalyst possessed the highest number of acidic sites. La promotion improved the Co dispersion, while Mg promotion enhanced the metal support integration. La-promoted catalysts are deactivated because of active metal oxidation and the generation of hard carbon. The carbon was deposited in all catalysts; however, the activity of the Mg-promoted catalyst was unaffected. The intermediate surface basicity and strong metal support interaction improved the Mg-promoted catalyst's stability. The La and Mg-promoted catalysts possessed lower apparent activation energies.

Summary: Developing active and stable catalysts for carbon-free hydrogen production is crucial to mitigate the effects of climate change. Ammonia is a promising carbon-free hydrogen source, as it has a high hydrogen content and is liquid at low pressure, which allows its easy storage and transportation. We have recently developed a nickel-based catalyst with a small content of ruthenium supported on cerium oxide, which exhibits high activity and stability in ammonia decomposition. Here, we investigate mechanochemical milling for its synthesis, a faster and less energy-consuming technique than conventional ones. Results indicate that mechanochemical synthesis increases catalytic activity compared to the conventional incipient wetness impregnation method. The interaction between the metal precursors and the support is key in fine-tuning catalytic activity, which increases linearly with oxygen vacancies in the support. Moreover, the mechanochemical method modifies the oxidation state of Ni and Ru species, with a variation depending on the precursors.

Summary: While photocatalytic technology has brought additional opportunities and possibilities for the green conversion and sustainable development of ammonium-based nitrogen fertilizers, the low activation efficiency of the molecular N2 has impeded its further application feasibility. Here to address the concern, we designed an amorphous molybdenum hydroxide anchored on the ultrathin magnesium-aluminum layered double hydroxide (Mo@MgAl-LDH) nanosheets for benefiting the N2 photofixation to NH3. With the aid of the designed amorphous Mo(V) species, the pristine MgAl-LDH exhibited a considerable performance of nitrogen photofixation under visible light irradiation (NH3 production rate of 114.4 μmol g−1 h−1) due to the improved N2 activation efficiency. The work demonstrated a feasible strategy for nitrogen photofixation using amorphous Mo(V) species, which may also deliver a novel inspiration for the development of amorphous photocatalysts toward the photoactivation of molecular N2.

TUD-1, a novel sponge-like three-dimensional mesoporous silica material, was synthesized in one-step using a hydrothermal technique and triethanolamine as a template. To enhance its acidic properties, the TUD-1 material underwent sulfonation with varying amounts of sulfonic groups (1 and 3 wt%). Structural characteristics were determined using XRD, FTIR, Raman, BET analysis, HRTEM, SEM, and XPS. Surface acidities of the catalysts were evaluated through non-aqueous potentiometric titration and FTIR analysis of chemisorbed pyridine. The performance of catalysts was assessed in various reactions, including the Pechmann reaction, Friedel-Crafts acylation reaction, and Biginelli reaction for synthesis of 7-hydroxy-4-methyl-2H-chromen-2-one, aromatic ketones and 3, 4-dihydropyrimidin-2(1H)-one. The findings confirm that the TUD-1 mesoporous structure did not undergo any significant alteration post sulfonation. The sulfonated catalysts exhibited higher surface acidities than TUD-1. A correlation between surface acidity, particularly Brönsted acid sites, and catalytic efficiency in selected reactions was evident from both catalytic testing and characterization. Under moderate conditions, TUD-1-3SO3H exhibited outstanding catalytic performance and remarkable reusability across all selected reactions.

Summary: Electrocatalysts undergo structural evolution under operating electrochemical CO2 reduction reaction (CO2RR) conditions. This dynamic reconstruction correlates with variations in CO2RR activity, selectivity, and stability, posing challenges in catalyst design for electrochemical CO2RR. Despite increased research on the reconstruction behavior of CO2RR electrocatalysts, a comprehensive understanding of their dynamic structural evolution under reaction conditions is lacking. This review summarizes recent developments in the dynamic reconstruction of catalysts during the CO2RR process, covering fundamental principles, modulation strategies, and in situ/operando characterizations. It aims to enhance understanding of electrocatalyst dynamic reconstruction, offering guidelines for the rational design of CO2RR electrocatalysts.

Summary: The electrochemical carbon dioxide reduction (CO2RR) on Cu-based catalysts is a promising strategy to store renewable electricity and produce valuable C2+ chemicals. We investigate the CO2RR on Cu-Ag nanostructures that have been electrodeposited in a green choline chloride and urea deep eutectic solvent (DES). We determine the electrochemically active surface area (ECSA) using lead underpotential deposition (UPD) to investigate the CO2RR intrinsic activity and selectivity. We show that the addition of Ag on electrodeposited Cu primarily suppresses the production of hydrogen and methane. While the production of carbon monoxide slightly increases, the partial current of the total C2+ products does not considerably increase. Despite that the production rate of C2+ is similar on Cu and Cu-Ag, the addition of Ag enhances the formation of alcohols and oxygenates over ethylene. We highlight the potential of metal electrodeposition from DES as a sustainable strategy to develop bimetallic Cu-based nanocatalysts for CO2RR.

Summary: Synergetic management of waste activated sludge, heavy metals (HMs) and CO2 for their valorization and cyclic utilization is rarely reported. Herein, we employed sludge-derived extracellular polymeric substances (EPS) and HMs in wastewater to fabricate a gas diffusion electrode (GDE) for electrochemical CO2 reduction. This approach atomically dispersed Ni at each nanofiber of the GDE. Abundant N element in the EPS proved to play a key role in the formation of Nx-Ni (mixture of N3-Ni and N4-Ni) sites for highly efficient CO2 to CO conversion. The atomical Ni3+ shows high catalytic activity. Direct gaseous CO2 reduction in a membrane electrode assembly generated a current density up to 50 mA·cm−2 with CO:H2 ratio of ∼100 and ∼75% FECO under 2.69 cell voltage. This strategy takes advantage of all waste streams generated on site and consolidates traditionally separated treatment processes to save costs, produces value-added products and generates carbon benefits during wastewater treatment.

Summary: Photothermal conversion represents one crucial approach for solar energy harvesting and its exploitation as a sustainable alternative to fossil fuels; however, an efficient, cost-effective, and generalized approach to enhance the photothermal conversion processes is still missing. Herein, we develop a feasible and efficient photothermal conversion strategy that achieves simultaneous light and heat management using supported metal clusters and WSe2 interlayer toward enhanced CO2 hydrogenation photothermal catalysis. The interlayer can simultaneously reduce heat loss in the catalytic layer and improve light absorption, leading to an 8-fold higher CO2 conversion rate than the controls. The optical and thermal performance of WSe2 interlayered catalysts on different substrates was quantified using Raman spectroscopy. This work demonstrates a feasible and generalized approach for effective light and heat management in solar harvesting. It also provides important design guidelines for efficient photothermal converters that facilitate the remediation of the energy and environmental crises faced by humans.

Summary: The exploration of renewable alternatives to fossil fuels for chemical production is indispensable to achieve the ultimate goals of sustainable development. Chitin biomass is an abundant platform feedstock that naturally bears both nitrogen and carbon atoms to produce nitrogen-containing chemicals (including organonitrogen ones and inorganic ammonia). The expansion of biobased chemicals toward nitrogen-containing ones can elevate the economic competitiveness and benefit the biorefinery scheme. This review aims to provide an up-to-date summary on the overall advances of the chitin biorefinery for nitrogen-containing chemical production, with an emphasis on the design of the catalytic systems. Catalyst design, solvent selection, parametric effect, and reaction mechanisms have been scrutinized for different transformation strategies. Future prospectives on chitin biorefinery have also been outlined.

Summary: Hydrodesulfurization (HDS) is a commonly used route for producing clean fuels in modern refinery. Herein, ammonium/amine-intercalated MoS2 catalysts with various content of 1T phase and S vacancies have been successfully synthesized. Along with the increment of 1T phase and S vacancies of MoS2, the initial reaction rate of the HDS of dibenzothiophene (DBT) can be improved from 0.09 to 0.55 μmol·gcat−1·s−1, accounting for a remarkable activity compared to the-state-of-the-art catalysts. In a combinatory study via the activity evaluation and catalysts characterization, we found that the intercalation species of MoS2 played a key role in generating more 1T phase and S vacancies through the ‘intercalation-deintercalation’ processes, and the hydrogenation and desulfurization of HDS can be significantly promoted by 1T phase and S vacancies on MoS2, respectively. This study provides a practically meaningful guidance for developing more advanced HDS catalysts by the intercalated MoS2-derived materials with an in-depth understanding of structure-function relationships.

The development of electrocatalysts with high catalytic performance and low costs for oxygen reduction reaction (ORR) is still challenging. Herein, an overall solution for ORR in alkaline media, from the catalyst synthesis to catalyst regeneration and to the development of a rapid, reliable and easy approach for electrode surface evaluation, is presented. We focused on the development and characterization of an efficient material for ORR in alkaline media, α-Fe2O3 N-doped graphene (Fe-N-Gr). The associative pathway for the four electron transfer ORR mechanism is sustained by the Raman spectra recorded from the electrode surface. We highlighted the possibility of catalyst regeneration by a simple electrochemical method. After two regeneration rounds and 1500 cycles in O2-saturated 1 M NaOH, the catalyst still retains 40.8 % catalytic activity. Finally, as a part of the overall solution, we demonstrated that a methodology based on Raman spectroscopic measurements and machine learning algorithms can be applied for graphene-based catalysts lifetime investigation.

Fe-based Fischer-Tropsch Synthesis (FTS) enables the selective conversion of syngas into long-chain hydrocarbons, which can be further refined to produce highly demanded liquid fuels and high-value chemical products. However, developing novel heterogeneous catalysts for FTS with desirable performance characteristics is a challenging task, as their performance depends on various factors such as precursor, support material, promoters, pretreatment conditions and the catalyst structures. Thus, it remains difficult to understand the structure-performance relationship of FTS and to optimize the catalyst formulations and operating conditions rationally. By integrating traditional chemistry with machine learning, we herein establish intrinsic correlations among reduction, reaction conditions, phase information and the methane selectivity of Fe-based FTS, using high quality experimental data. The content of the iron phases in the post-reaction phase, particularly χ-Fe5C2, significantly influences the methane selectivity of the catalyst. Four types of additives K, Cu, SiO2, and Ca could effectively suppress the methane selectivity, most likely by promoting or stabilizing the iron carbide phases, indicated by their strong correlation. The machine learned structure-performance relationships offers new insights into the design of Fe-based FTS catalysts, and could guide the further optimization of the preprocessing conditions and various parameter factors to minimize the methane selectivity of FTS.

The hydrogen bond (HB) catalysed Diels-Alder (DA) reactions of acrolein with cyclopentadiene have been investigated within the Molecular Electron Density Theory (MEDT) at the ωB97X-D/6-311G(d,p) computational level. The formation of HBs increases the electrophilicity of these species, suggesting an acceleration of these polar Diels-Alder (P-DA) reactions with forward electron density flux. Formation of one or two HBs with acrolein decreases the activation energies of the HB-catalysed P-DA reactions by 1.7 (methanol) and 4.0 (squaramide) kcal·mol−1, with the corresponding DA reactions exhibiting low endo stereoselectivity. These HB-catalysed DA reactions proceed through non-concerted one-step mechanisms via asynchronous transition state structures (TSs). An Interacting Quantum Atoms (IQA) energy partitioning analysis of the TSs indicates that the intra-atomic stabilization of the acrolein framework, coupled with the increase of the global electron density transfer, plays a crucial role in reducing the activation energies of these HB-catalysed DA reactions.

Catalytic carbon dioxide (CO2) conversion technologies can be important components in carbon capture, storage and utilization for CO2 mitigation and possible future economic activity and have gained significant attention globally in past decades. Electrified non-thermal plasma (NTP) catalysis enables CO2 hydrogenation into value-added chemicals under mild conditions. If the hybrid process is coupled with renewable energy and green hydrogen, it can be the promising solution to address the energy and carbon emission challenges. To enhance the energy efficiency of NTP-catalytic systems, bespoke catalyst design and process optimization are necessary. Here, using Ni catalysts supported on mesoporous MCM-41 and NTP-catalytic CO2 methanation as the model systems, the effects of Ni metal dispersion, argon (Ar) addition and residence time on the NTP catalysis were also studied. The findings show that (i) increased metal dispersion alone did not lead to significant enhancement in the performance of NTP catalysis (e.g., CH4 production rate: 31.4 × 10−5 mol/(s·gNi) for 42.6 % Ni dispersion vs. 26.8 × 10−5 mol/(s·gNi) for 25.1 % dispersion), (ii) Ar addition to the system led to the decreased methane production rate (e.g., CH4 selectivity decreased by ∼19 % due to the increase in Ar addition to the system from 5 to 50 mL/min), and (iii) optimization of the residence time could improve the performance of NTP-catalytic CO2 methanation (i.e., an extension of the residence time to 0.69 s resulted in the higher CO2 conversion of 72.7 % and CH4 selectivity of 95.9 % at 9.6 kV than that at 0.49 s and 11 kV).

Summary: Hydrogen generation from boron hydride is important for the development of hydrogen economy. Cobalt (Co) element has been widely used in the hydrolysis of boron hydride. Pyrolysis is a common method for materials synthesis in catalytic fields. Herein, Co-based nanocomposites derived from the pyrolysis of organic metal precursors and used for hydrolysis of boron hydride are summarized and discussed. The different precursors consisting of MOF, supported, metal, and metal phosphide precursors are summarized. The catalytic mechanism consisting of dissociation mechanism based on oxidative addition-reduction elimination, pre-activation mechanism, SN2 mechanism, four-membered ring mechanism, and acid-base mechanism is intensively discussed. Finally, conclusions and outlooks are conveyed from the design of high-efficiency catalysts, the characterization of catalyst structure, the enhancement of catalytic activities, the investigation of the catalytic mechanism, and the catalytic stability of active structure. This review can provide guidance for designing high-efficiency catalysts and boosting development of hydrogen economy.

Summary: The distinct folding accompanied by its polymorphic character renders DNA G-quadruplexes promising biomolecular building blocks to construct novel DNA-based and supramolecular assemblies. However, the highly polar nature of DNA limits the use of G-quadruplexes to water as a solvent. In addition, the archetypical G-quadruplex fold needs to be stabilized by metal-cations, which is usually a potassium ion. Here, we show that a noncovalent PEGylation process enabled by electrostatic interactions allows the first metal-free G-quadruplexes in organic solvents. Strikingly, incorporation of an iron-containing porphyrin renders the self-assembled metal-free G-quadruplex catalytically active in organic solvents. Hence, these “supraG4zymes” enable DNA-based catalysis in organic media. The results will allow the broad utilization of DNA G-quadruplexes in nonaqueous environments.

Summary: Zeolite-encaged metal nanoparticles (NPs) catalysts are emerging as a new frontier owing to their superior ability to stabilize the structure and catalytic performance in the thermal and environmental catalytic reaction. However, the pore size below 2 nm of the conventional zeolites usually limits the accessibility of metal active sites. Herein, Co-Cu NPs of about 2.5–3.5 nm were uniformly encapsulated in the intracrystalline mesoporous Silicalite-1 (S-1) through alkali-treatment ligand-assisted strategy. The obtained sample (termed CoxCu1-x@HS-1) exhibited efficient activity and stability in the ammonia borane hydrolysis with the highest TOF value of 21.46 molH2·molMe−1·min−1. UV–vis DRS spectra indicated that intracrystalline mesopores have greatly improved the openness and accessibility of the active sites, thus improving their catalytic performance. The introduction of Cu regulates the electronic properties of Co, further increasing hydrogen production activity. This research creates new prospects to design other high-performance hierarchical porous zeolite-confined metal/metal oxide catalysts.

Summary: Acidic and basic sites of catalysts are essential for CO2 capture and activation. In this work, Zr, N-ZnO/ZnAl-LDH-IL composites in ionic liquid and methanol systems were fabricated, and applied to catalyze the synthesis of ethylene carbonate (EC) from ethylene glycol (EG) and CO2 with about 4.76 mmolEC gCat.−1 h−1. The composites showed more strong basic sites due to the effective induction of reactive groups on the catalyst surface by Zr doping, resulting in an increase of pyridinic-N groups from 5.48% to 22.25%. More C atoms adjacent to pyridinic-N as strong basic sites was conducive to the activation of CO2 and EG. In addition, the possible catalytic pathway and mechanism of the composites for synthesizing EC as well as the doping of La, Fe, Ce, and Cu were also investigated, which provides an effective strategy for regulating the acid-base centers on the catalyst surface through ionic liquids and methanol solvents.

Summary: Light olefins are key intermediates in the synthesis of petrochemicals, and the conversion of stabilized carbon dioxide to light olefins using catalysts containing halogenated elements such as chlorine is a major challenge. Building on previous reports emphasizing the toxic effects of halogen elements on catalysts, we present the synthesis of FeMnKBr/YNa catalysts. This involved the synthesis of the catalyst by melt permeation using Br-containing potassium salts, other metal nitrates and YNa zeolites. The catalyst performed well in converting syngas (H2/CO2 = 3) to light olefins with a selectivity of 56.2%, CO2 conversion of 34.4%, and CO selectivity of 13.6%. Adding Br aids in reducing the Fe phase, boosts catalyst carburization, and produces more iron carbide species. It also moderately deposits carbon on the active center’s surface, enhancing active phase dispersion. Br’s electronegativity mitigates the influence of K, reducing catalyst’s carbon-carbon coupling ability, leading to more low-carbon olefins generation.

Summary: Constructing platinum-like materials with excellent catalytic activity and low cost has great significance for hydrogen evolution reaction (HER) during electrolysis of water. Herein, palladium nanoparticles (NPs) deposition on the surface of Co NPs using nitrogen-doped carbon (NC) as substrate, denoted as N-ZIFC/CoPd-30, are manufactured and served as HER electrocatalysts. Characterization results and density functional theory calculations validate that Pd-Co heterojunctions with NC acting as “electron donators” promote the Pd species transiting to the electron-rich state based on an efficient electron transfer mechanism, namely the N-C polar bonds induced strong metal-support interaction effect. The electron-rich Pd sites are beneficial to HER. Satisfactorily, N-ZIFC/CoPd-30 have only low overpotentials of 16, 162, and 13 mV@-10 mA cm−2 with the small Tafel slopes of 98 mV/decade, 126 mV/decade, and 72 mV/decade in pH of 13, 7, and 0, respectively. The success in fabricating N-ZIFC/CoPd opens a promising path to constructing other platinum-like electrocatalysts with high HER activity.

Summary: Programmable catalysis—the purposeful oscillation of catalytic potential energy surfaces (PES)—has emerged as a promising method for the acceleration of catalyzed reaction rates. However, theoretical study of programmable catalysis has been limited by onerous computational demands of integrating the stiff differential equations that describe periodic cycling between PESs. This work details methods that reduce the computational cost of finding the limit cycle by ≳108×. These methods produce closed-form analytical solutions for didactic case studies, examination of which provides physical insights of programmable catalysis mechanisms. Generalization of these analyses to more complex reaction networks, including CO oxidation on Pt (111) surfaces, exposes the key catalyst properties required to achieve enhanced rates and conversions via one of two programmable catalysis mechanisms: quasi-static (high frequency) and stepwise (intermediate frequency). Analytical description of each mechanism is critical in understanding the consequences of the Sabatier principle on achievable rate enhancement through programmed catalysis.

Summary: Polyoxometalates (POMs) have been well studied and explored in electro/photochemical water oxidation catalysis for over a decade. The high solubility of POMs in water has limited its use in homogeneous conditions. Over the last decade, different approaches have been used for the heterogenization of POMs to exploit their catalytic properties. This study focused on a Keggin POM, K6[CoW12O40], which was entrapped in a sol-gel matrix for heterogeneous electrochemical water oxidation. Its entrapment in the sol-gel matrix enables it to catalyze the oxygen evolution reaction at acidic pH, pH 2.0. Heterogenization of POMs using the sol-gel method aids in POM’s recyclability and structural stability under electrochemical conditions. The prepared sol-gel electrode is robust and stable. It achieved electrochemical water oxidation at a current density of 2 mA/cm2 at a low overpotential of 300 mV with a high turnover frequency (TOF) of 1.76 [mol O2 (mol Co)−1s−1]. A plausible mechanism of the electrocatalytic process is presented.

Summary: The development of electrosynthetic technologies for H2O2 production is appealing from a sustainability perspective. The use of carbonate species as mediators in water oxidation to peroxide has emerged as a viable route to do so but still many questions remain about the mechanism that must be addressed. To this end, this work combines electrochemical and spectroscopic methods to investigate reaction pathways and factors influencing the efficiency of this reaction. Our results indicate that CO32− is the key species that undergoes electrochemical oxidation, prior to reacting with water away from the catalyst. Through spectroelectrochemical experiments, we noted that CO32− depletion is a factor that limits the selectivity of the process. In turn, we showed how the application of pulsed electrolysis can augment this, with an initial set of optimized parameters increasing the selectivity from 20% to 27%. In all, this work helps pave the way for future development of practical H2O2 electrosynthetic systems.