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Formamides are important feedstocks for the manufacture of many fine chemicals. State‐of‐the‐art synthesis of formamides relies on the use of an excess amount of reagents, giving copious waste and thus poor atom‐economy. Here, we report the first example of direct synthesis of N‐formamides by coupling two challenging reactions, namely reductive amination of carbonyl compounds, particularly biomass‐derived aldehydes and ketones, and fixation of CO2 in the presence of H2 over a metal‐organic framework supported ruthenium catalyst, Ru/MFM‐300(Cr). Highly selective production of N‐formamides has been observed for a wide range of carbonyl compounds. Synchrotron X‐ray powder diffraction reveals the presence of strong host‐guest binding interactions via hydrogen bonding and parallel‐displaced π⋅⋅⋅π interactions between the catalyst and adsorbed substrates facilitating the activation of substrates and promoting selectivity to formamides. The use of multifunctional porous catalysts to integrate CO2 utilisation in the synthesis of formamide products will have a significant impact in the sustainable synthesis of feedstock chemicals. [ABSTRACT FROM AUTHOR]

We report an investigation of catalyst performance for the decomposition of ammonia under industrially relevant conditions (high temperatures of up to 800 °C and an elevated pressure of 5 bar) with further emphasis on their stability at high reaction temperatures. The catalysts were applied and tested as coatings in 500 µm wide channels of microreactors. Nickel-based catalysts were studied and compared to a ruthenium-based catalyst supported on SiO2. The effect of the support on the catalytic performance was investigated, and CeO2-supported nickel catalysts were found to exhibit the highest activity. Promoters were applied to increase the NH3 decomposition activity of the Ni/CeO2 catalysts. The addition of cesium led to a slight reduction in activity, while lanthanum, calcium, and barium doping resulted in increased activity. In particular, the barium-doped Ni/CeO2 catalyst showed very high ammonia conversion and closed the activity gap with respect to ruthenium catalysts at reactor temperatures of 650 °C and higher. The hydrogen production rates achieved in this work were compared to values in the literature and were shown to exceed values found earlier for both nickel- and ruthenium-based catalysts. Furthermore, the ruthenium-based catalysts under investigation were rapidly deactivated at 700 °C, while the nickel-based catalysts did not show deactivation after 220 h on time on stream at 700 °C. [ABSTRACT FROM AUTHOR]

Hyperbranched polymer–supported ruthenium NPs were used for hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) in water. The catalytic nanocomposite showed 99.9% LA conversion and 100% GVL selectivity under mild conditions and low Ru loading in batch reactor under H2. Ru NPs formed in situ during the hydrogenation of LA demonstrated the higher catalytic activity over pre-synthesized Ru NPs. Superior catalytic properties of Ru nanocomposites are attributed both to the formation of small Ru NPs and to the effect of pyridine containing polymer support, which provides a reliable dispersion of Ru species over support and at the same time due to weak alkalinity, promotes interaction with LA thereby facilitating catalytic reaction. The functional hyperbranched polymer contributes to high stability of supported Ru NPs which was demonstrated in six consecutive catalytic cycles. TEM, XPS, EDS, XRD were used to analyze the structure, NPs distribution, and oxidation state of Ru catalysts before and after catalytic reactions. [ABSTRACT FROM AUTHOR]

To meet the increasing demand for small-scale NH3 production, catalysts that work under milder conditions than those of the Haber–Bosch process are essential. In this study, Ru clusters and nanoparticles were impregnated on five different CeO2 supports to prepare Ru/CeO2 catalysts for NH3 synthesis at 400 °C and 0.1 MPa. The basicity of the CeO2 support and Ru particle size significantly influenced the catalytic activity. The catalytic activity increased with decreasing Ru particle size, reaching the maximum of ~ 200 mmol gRu−1 h−1 at ~ 1 nm, which is ascribed to a high proportion of unique active sites different from the B5-type sites. Our findings demonstrate that Ru cluster catalysts are advantageous over Ru nanoparticle catalysts for NH3 synthesis. [ABSTRACT FROM AUTHOR]

Catalytic performances of Ru nanoparticles (NPs) on the oxides can be remarkably regulated by the surface properties of oxide supports. Herein, we show that activity of Ru NPs on γ-Al2O3 can be enhanced via generation of superbasic sites on the γ-Al2O3 support by K doping (K‒Al2O3). The optimized Ru/K‒Al2O3 catalyst achieves a hydrogen production rate of 25.2 mmol gcat−1 min−1 at 450 °C. The Ru/K‒Al2O3 catalyst also gives highly stable performance for over 120 h. Characterization results show that the presence of superbasic sites induce much enhanced interaction between Ru NPs and K‒Al2O3 support. Moreover, the surface superbasic sites play a key role in modulating electronic property of Ru NPs, which can promote electron donation from support to Ru NPs and greatly enhance the intrinsic activity of the Ru NPs. The use of K‒Al2O3 superbase for Ru-based ammonia decomposition catalysts are expected to expand the application of solid superbase materials. [ABSTRACT FROM AUTHOR]

The introduction of heteroatoms into manganese dioxide (MnO2) is an effective method to adjust the active site of electrochemical water oxidation catalysis. Although many modification methods for MnO2 have been studied in electrocatalytic oxygen evolution reaction (OER), few studies have focused on the influence of regulating different crystal forms of MnO2 on catalytic activity. This article prepared four different crystal forms of MnO2 (α-MnO2, β-MnO2, γ-MnO2 and δ-MnO2), and systematically studied the catalytic performance of the catalyst (x-MnO2-Ru) prepared by adding Ru to α-MnO2, β-MnO2, γ-MnO2 and δ-MnO2 for OER. The results of linear sweep voltammetry and chronopotentiometry measurements show that the catalyst prepared by adding Ru to β-MnO2 (β-MnO2-Ru) has the best electrochemical performance. β-MnO2 -Ru shows a low overpotential (300 mV at 10 mA·cm-2) and outstanding catalytic activity with small degradation after 24 h operation. It is found that β-MnO2-Ru exhibits excellent electrocatalytic performance due to its abundance of Mn3+ and defect oxygen vacancies. [ABSTRACT FROM AUTHOR]

Aqueous phase selective hydrogenation of cinnamaldehyde (CALD), as a representative α,β-unsaturated aldehyde, into cinnamyl alcohol (CALA) has been investigated over monometallic Ru and bimetallic RuCo catalysts on pristine h-BN support. Using water as the solvent, the optimal 0.5%Ru-1.1%Co/h-BN catalyst exhibits 510 h−1 specific reaction rate and 78.9 % CALA selectivity as well as good recycling stability at 100 °C. Based on the structure characterizations of catalysts, metal nanoparticles consisting of metallic Ru0 and partially oxidized Ruδ+ sites are uniformly dispersed on h-BN thin sheets. In comparison to monometallic catalysts, additive Co metals in bimetallic RuCo/h-BN catalysts play significant geometric and electronic modification roles on Ru active sites depending on the Ru/Co ratio, and therefore remarkably enhances the preferential activation of CALD C O bond and selectivity of CALA product as well as accelerates the catalytic reaction. Furthermore, the hydrogen dissociative activation ability of various Ru and RuCo catalysts was evaluated, while the superior catalytic performance in water than other commonly used solvents was also clarified and discussed. [Display omitted] • h-BN-supported bimetallic RuCo catalyst exhibits high activity and selectivity in cinnamaldehyde C O hydrogenation. • Co additive metal plays geometric and electronic modification roles on Ru active site. • Partially oxidized Ruδ+ and decorated CoO x serve as Lewis acid sites for enhancing C O activation. • Hydrogen dissociative activation ability can be promoted by bimetallic RuCo catalyst. • Water as the solvent plays multiple positive roles of polarizing C O bond and hydrogen transfer. [ABSTRACT FROM AUTHOR]

Fischer Tropsch synthesis (FTS) is a promising catalytic solution to achieve ultra-clean fuel in which catalyst has a significant role. Even though several kinetic models have been rendered for it, representing a new one based on a meticulous mechanism is noteworthy, particularly when employing a novel catalyst. Hence, in this work, molecular dynamic (MD) simulation is utilized to identify the appropriate pathway from the viewpoint of minimum energy of the elementary reactions. In this regard, we consider a majority of plausible FTS elementary reactions over Ru–CO@C(Z-d)@void@CeO 2 (cobalt carbon-MOF based plus ruthenium and ceria with porous structure) catalyst, and by employing MD computations forward and reverse activation energy barrier values for each reaction are evaluated. Then, based on the minimum energy pathway (MEP), the appropriate mechanism is derived, which is inferred from the H-assisted CO dissociation pathway for the beginning step. Subsequently, a kinetic model is developed based on this mechanism, and the model parameters are correlated and optimized employing the genetic and Levenberg-Marquardt algorithms, respectively. In addition, we use various statistical methods to assess the significance of the model. For instance, the Mean Absolute Percentage Deviation (MAPD) of the correlated values from the experimental value is 4.46%. Additionally, the relative residual percentage (RR%) plots illustrate that 99% of the correlated data have less than a 10% deviation. [Display omitted] • Rendering a comprehensive kinetic model based on an evaluated mechanism for Fischer Tropsch Synthesis. • Presenting a mechanism by evaluating the minimum energy pathway using Molecular dynamic computations. • Evaluating the H-assisted CO dissociation pathway meticulously. • Assessing the significance of the model employing statistical methods. [ABSTRACT FROM AUTHOR]

To synthesize highly dispersed Ru nanoparticles (NPs) with desired particle size for NH 3 decomposition, an appropriate support is crucial. Herein, spherical mesoporous silica (SMS) NPs with ∼3 nm pores are synthesized by a microwave-assisted evaporation-induced self-assembly method and used as support of Ru NPs for NH 3 decomposition. Characterization shows that compared to Ru NPs supported on SBA-15 and fumed SiO 2 , Ru NPs supported on SMS (Ru@SMS) exhibit superior NH 3 decomposition performance, achieving a hydrogen generation rate of 31.4 mmol·g-1 cat·min−1 at 500 °C, which is one of the highest reported values for supported Ru catalysts in NH 3 decomposition. The excellent NH 3 decomposition performance observed on Ru@SMS should be attributed to effective dispersion and appropriate particle size (2.22 ± 0.29 nm) of Ru NPs. This work highlights the potential of SMS as support of Ru catalyst in NH 3 decomposition. • SMS NPs with ∼3 nm pores are synthesized by a microwave-assisted EISA method. • The highly dispersed Ru NPs have mean particle size of 2.22 ± 0.29 nm. • Ru@SMS achieves a hydrogen generation rate of 31.4 mmol·g-1 cat·min−1 at 500 °C. • Ru@SMS shows a marginal decrease in NH 3 conversion over a 128-h period. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) is an ideal substitute to commercial Pt/C for hydrogen evolution reaction (HER). Reducing the size of Ru to clusters can greatly increase the utilization of atoms, however, over‐strong RuH binding will be brought about. Additionally, the water dissociation ability of Ru clusters is unfavorable, leading to unsatisfactory activity in alkaline and neutral HER. Herein, a rational and versatile design strategy is proposed by exploring supports with both high work function and facilitated water dissociation ability to boost the pH‐universal HER activity of Ru clusters. As exemplified by Mo2C, density functional calculations verify that the introduction of Mo2C support can optimize the hydrogen adsorption energy and promote the kinetics of water dissociation. Guided by theoretical calculations, heterostructured Mo2C nanoparticles‐Ru clusters anchored carbon spheres (Mo2C‐Ru/C) are designed and prepared. A low overpotential of 22 mV at 10 mA cm−2 and a small Tafel slope of 25 mV dec−1 in alkaline solution is demonstrated by Mo2C‐Ru/C. The Mo2C‐Ru/C also exhibits excellent activity in alkaline seawater, acidic, and neutral solutions. When assembling Mo2C‐Ru/C with Zn foil to construct an alkaline‐acid Zn‐H2O battery, the as‐fabricated battery presents high discharge power density and excellent stability for simultaneous generation of electricity and hydrogen (H2). [ABSTRACT FROM AUTHOR]

This document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry." It includes various articles and papers on topics such as supramolecular chemistry, carbon-hydrogen bond activation, coordination modes of ligands, and catalysis. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a brief overview of the articles and papers included in the journal issue. [Extracted from the article]

Two rigid β-elimination immune PCcarbeneP pincer ligands, differing in their electron donor properties by variation of the substitution pattern on the aromatic linker arms, were complexed to ruthenium to form the dichlorides LRRuCl2 (R = H or NMe2). These compounds were converted to hydrido chlorides by treatment with dihydrogen (H2) and a base. By converting to tert-butoxide derivatives in situ under an atmosphere of H2, the poly hydride PCalkylP complexes LHRRu(H)3 compounds were generated. In these complexes, H2 has added across the Ru＝C bond in the PCcarbeneP starting materials. The polyhydrides are dynamic in solution and extensive NMR studies helped to elucidate the speciation and fluxional processes operative in this dynamic system. The polyhydride complexes react rapidly with CO2 to give the PCcarbeneP formato hydride complexes LRRu(H)-κ2-O2CH. For R = H, the 1,2-hydride shift from the anchoring alkyl of the PCalkylP carbon to the metal is reversible, but for R = NMe2 it is irreversible. The CO2 incorporated into the formato ligand of these compounds exchanges with free CO2via a bimolecular mechanism that is more rapid for R = NMe2 than for R = H; plausible explanations for this observation are proffered. Experiments designed to evaluate the efficacy of the R = NMe2 formato hydride complex as a catalyst precursor for CO2 hydrogenation to formate salts reveal poor performance in comparison to state-of-the-art ruthenium-based catalysts. This is due primarily to the precipitation of a dimeric μ-κ2-κ1-CO3 carbonate complex that is not an active catalyst for the reaction. [ABSTRACT FROM AUTHOR]

Two rigid β-elimination immune PCcarbeneP pincer ligands, differing in their electron donor properties by variation of the substitution pattern on the aromatic linker arms, were complexed to ruthenium to form the dichlorides LRRuCl2 (R = H or NMe2). These compounds were converted to hydrido chlorides by treatment with dihydrogen (H2) and a base. By converting to tert-butoxide derivatives in situ under an atmosphere of H2, the poly hydride PCalkylP complexes LHRRu(H)3 compounds were generated. In these complexes, H2 has added across the Ru＝C bond in the PCcarbeneP starting materials. The polyhydrides are dynamic in solution and extensive NMR studies helped to elucidate the speciation and fluxional processes operative in this dynamic system. The polyhydride complexes react rapidly with CO2 to give the PCcarbeneP formato hydride complexes LRRu(H)-κ2-O2CH. For R = H, the 1,2-hydride shift from the anchoring alkyl of the PCalkylP carbon to the metal is reversible, but for R = NMe2 it is irreversible. The CO2 incorporated into the formato ligand of these compounds exchanges with free CO2via a bimolecular mechanism that is more rapid for R = NMe2 than for R = H; plausible explanations for this observation are proffered. Experiments designed to evaluate the efficacy of the R = NMe2 formato hydride complex as a catalyst precursor for CO2 hydrogenation to formate salts reveal poor performance in comparison to state-of-the-art ruthenium-based catalysts. This is due primarily to the precipitation of a dimeric μ-κ2-κ1-CO3 carbonate complex that is not an active catalyst for the reaction. [ABSTRACT FROM AUTHOR]

We report the development of Ru/Mg–Al oxide coated metal-structured catalysts with excellent heat and mass transfer characteristics for efficient clean H 2 production from ammonia decomposition. Ammonia is a promising carrier for the mass transport of hydrogen and facilitates the production of COx-free hydrogen by decomposing into nitrogen and hydrogen. Ru nanoparticles are uniformly dispersed on the Mg–Al oxide layer of the FeCralloy monoliths and foams via precipitation. The catalytic activities depend on the surface area and loading of the catalysts and the metal dispersion in the oxide layer. At temperatures <650 °C, and a gas hourly space velocity (GHSV) of 3,000 h−1, monolithic catalysts with a large surface area and evenly distributed active metals perform excellently. Foam catalysts with excellent heat transfer performance better at temperatures >650 °C and GHSV >6,000 h−1. Foam catalyst stability is verified for 100 h in a 20 Nm3/h high-purity hydrogen production system. [Display omitted] • COx-free H 2 production via NH 3 decomposition on Ru-coated metal-structured catalysts. • Nano-sized Ru uniformly dispersed in plate-like Mg–Al oxide layers by precipitation. • Amount of Ru in the structured catalyst was <∼1/10 of that in the pellet catalyst. • Foams performed better catalytically than monoliths at higher GHSV (6,000 h−1). • Foam catalyst stability was verified in a 20 Nm3/h-H 2 production system for 100 h. [ABSTRACT FROM AUTHOR]

Ligand design is crucial for the design of robust and efficient molecular water oxidation catalysts (WOCs) based on metal complexes. Herein we report the water oxidation studies of a series of Ru WOCs bearing bipyridine dialkoxide ligands with different substituents. Combined with density functional theory (DFT) calculations, the proposed water oxidation mechanism is bimolecular coupling (I2M) of two seven‐coordinate (CN7) Ru=O species. The use of bulky phenyl groups on the planar alkoxide ligand helps to stabilize the high oxidation CN7 intermediates, without loss of ligand flexibility. This strategy may be useful for the design of other active WOCs. [ABSTRACT FROM AUTHOR]

A robust diphosphine-ruthenium(II) complex has been developed that can efficiently catalyze hydromethylation of N-heteroarenes to form N-methyl saturated N-heterocycles viz the reduction of N-heterocycles coupled with C–N bond formation. Both indoles and quinolines can be transformed to their corresponding N-methyl indolines and N-methyl 1,2,3,4-tetrahydroquinolines with high conversion (e.g., 12 indoles and 9 quinolines). On the basis of a series of experiments, a possible mechanism has been proposed to account for the hydrogenation and methylation processes involved in the catalytic pathway. More importantly, this approach provides a potential route for using DME as a methyl source for the production of N-methyl saturated N-heterocycles via hydromethylation. [ABSTRACT FROM AUTHOR]

[Display omitted] Bimetallic catalysts often outperform monometallic catalysts due to changeable structural orientation, synergistic effects, and integration of two different metal or metal oxide properties. Here, a series of CeO 2 nanorods (NR) supported bimetallic CuO x and RuO x catalysts (Cu: Ru ratios of 9:1, 7:3, and 5:5) were prepared using a wet impregnation method. In situ DRIFTS, H 2 temperature programmed reduction (H 2 -TPR), CO temperature programmed desorption (CO-TPD), and other characterization techniques were used to investigate the effect of the Cu:Ru ratio on the activity of low-temperature CO oxidation. Among three catalysts, CeO 2 NR supported 7 wt% Cu-3 wt% Ru catalyst after a reduction activation treatment showed the best performance with 100 % CO conversion at 166 °C and the lowest activation energy of 18.37 kJ mol−1. Raman and XPS profiles revealed that the origin of the superior performance is at least partially related to the high surface oxygen vacancy concentration and other distinct oxygen species (physi-/chemi-sorbed oxygen and bulk lattice oxygen), leading to outstanding adsorption and oxidation property of CO. [ABSTRACT FROM AUTHOR]

Dehydrogenation of ammonia borane to well-defined products is an important but challenging reaction. A dinuclear ruthenium complex with a Ru–Ru bond bearing a diazadiene (dad) unit and olefins as non-innocent ligands catalyzes the highly selective formation of conjugated polycondensed borazine oligomers (BxNxHy), predominantly B21N21H18, the BN analogue of superbenzene. [ABSTRACT FROM AUTHOR]

Designing highly active and durable catalysts is considered to be crucial for enhancing hydrogen evolution reaction (HER) from water electrolysis. Although some studies indicate that anatase TiO 2 is a promising candidate for electrolytic hydrogen evolution reaction, the influence of different crystalline phases of TiO 2 on the supported Ru catalysts for electrocatalytic HER performance is rarely systematically explored. Herein, a series of Ru/TiO 2 -X (X = R (Rutile), A (Anatase), and P25) catalysts were prepared to investigate the influence of the rutile and anatase phases of TiO 2 on the catalytic activity of Ru catalysts in HER. The findings demonstrate that the HER activity is much affected by the variation of the titania structure, when other factors are kept constant. The 15Ru/TiO 2 -R-H 2 has superior HER performance with a small overpotential of 63 mV to achieve a current density of 10 mA cm−2 in acidic electrolyte and 99 mV in alkaline electrolyte compared to 15Ru/TiO 2 -A-H 2 and 15Ru/TiO 2 -P25-H 2. This might be attributed to the faster electron transfer and lower Fermi level caused by the oxygen vacancy (V O) and strong metal-support interaction (SMSI), along with the exposure of active sites afforded by the highly dispersed ruthenium nanoparticles on the rutile TiO 2. Our results indicate that the presence of rutile TiO 2 support alone is adequate to maintain Ru in its most active form and make it a more performing catalyst, compared to anatase titania and P25. • Ru is supported on different crystalline phase of TiO 2 for electrocatalytic HER. • Partial Ru is incorporated the lattice of TiO 2 -R with SMSI effect. • Highly dispersed Ru and rich V O promote electrocatalytic HER. • Electron transfer from V O and Ti to surface Ru is conducive to optimizing HER. [ABSTRACT FROM AUTHOR]

Despite the fact that the technique of proton exchange membrane water electrolysis (PEMWE) dominates the market because of its low temperature of operation, platinum as a catalyst renders it relatively expensive. In this work, we demonstrated a recyclable ruthenium catalyst with high stability, high oxygen evolution reaction (OER) performance and low onset potential. In particular, instead of PEMWE, the technique of high temperature phosphoric acid water electrolysis (HT-PAWE) was used, with ruthenium oxide as its anode catalyst and a high operation temperature to decrease the amount of noble metals being used. Ruthenium was chosen in this study due to its excellent catalytic activity. The possibility of recycling and reusing noble metals would ease the problem of high cost. Homemade ruthenium catalyst in this study exhibited an outstanding OER performance including high stability and high current density than those of commercial platinum catalyst. Linear sweep voltammetry (LSV) test results showed that a maximum current density of 190 mA/cm2 was reached at only 1.5V SCE. For this experiment, ruthenium (III) chloride hydrate (RuCl 3 ·3H 2 O) was used as the precursor, and potassium chloride (KCl) and hydrochloric acid (HCl) acted as the supporting electrolyte. Pulsed electrodeposition was chosen to achieve a better control in particle size and distribution of the catalyst over selected specimens. After electrodeposition, the specimens underwent thermal treatment for increasing stability in catalyst particles. Scanning electron microscopy (SEM), linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were used to observe the morphology and to analyze the OER performance of the specimens, respectively. Types of catalyst carrier, electrodeposition potential and duration, and thermal treatment temperature were studied. As a result, all four parameters affected the morphologies and electrochemical performances of the tested specimens. • A pulsed electrodeposition method is adopted to prepare well dispersed Ru catalyst on Ti substrate. • Ruthenium catalyst by electrodeposition has higher OER performance than drop casted commercial Pt. • Appropriate temperature of heat treatment can improve catalyst stability. • The induced hydrogen bubbles during electrodeposition with negative potentials cause Ru catalyst to be dendritic. • Oxidation of carbon in carbon cloth at high potentials leads to worse catalyst stability. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Realizing the hydrogen economy by water electrolysis is an attractive approach for hydrogen production, while the efficient and stable bifunctional catalysts under high current densities are the bottleneck that limits the half‐cell reactions of water splitting. Here, we propose an approach of hydrothermal and thermal annealing methods for robust MoO2/MoNi4@Ru/RuO2 heterogeneous cuboid array electrocatalyst with multiplying surface‐active sites by depositing a monolayer amount of Ru. Benefiting from abundant MoO2/MoNi4@Ru/RuO2 heterointerfaces, MoO2/MoNi4@Ru/RuO2 heterogeneous cuboid array electrocatalysts effectively drive the alkaline water splitting with superior hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances. The synthesized MoO2/MoNi4@Ru/RuO2 has high HER activity, which realizes the working overpotentials of 48 mV at 50 mA·cm–2, further achieving overpotentials of 230 mV for industry‐level 1000 mA·cm–2 in alkaline water electrolysis. Moreover, it also showed an enhanced OER activity than commercial RuO2 with a small overpotential of 280 mV at 200 mA·cm–2 in alkaline media. When building an electrolyzer with electrodes of (–)MoO2/MoNi4@Ru/RuO2IIMoO2/ MoNi4@Ru/RuO2 (+), a cell voltage of 1.63 V and 1.75 V is just required to support the current density of 200 mA·cm–2 and 500 mA·cm–2 in alkaline water electrolysis, much lower than that of the electrolyzer of (–)Pt/CIIRuO2(+). This work demonstrates that MoO2/MoNi4@Ru/RuO2 heterogeneous nanosheet arrays are promising candidates for industrial water electrolysis applications, providing a possibility for the exploration of water electrolysis with a large current density. [ABSTRACT FROM AUTHOR]

Support effect is an important issue in heterogeneous catalysis, while the explicit role of a catalytic support is often unclear for catalytic reactions. A systematic density functional theory computational study is reported in this paper to elucidate the effect of a model boron nitride (BN) support on the first N-H bond activation step of NH3 on Run (n = 1, 2, 3) metal clusters. Geometry optimizations and energy calculations were carried out using density functional theory (DFT) calculation for intermediates and transition states from the starting materials undergoing the N-H activation process. The primary findings are summarized as follows. The involvement of the model BN support does not significantly alter the equilibrium structure of intermediates and transition states in the most favorable pathway (MFP). Moreover, the involvement of BN support decreases the free energy of activation, ΔG≠, thus improving the reaction rate constant. This improvement is more obvious at high temperatures like 673 K than low temperatures like 298 K. The BN support effect leading to the ΔG≠ decrease is most significant for the single Ru atom case among all three cases studied. Finally, the involvement of the model BN may change the spin transition behavior of the reaction system during the N-H bond activation process. All these findings provide a deeper insight into the support effect on the N-H bond activation of NH3 for the supported Ru catalyst in particular and for supported transition metal catalysts in general. [ABSTRACT FROM AUTHOR]

We reports the ex situ preparation of nanotitania supported ruthenium(0) nanoparticles (NPs) and their catalytic testing in dehydrogenation of dimethylamine borane (DMAB) in toluene solvent. Ru0/TiO 2 NPs are prepared following a 2-step process: Ru3+ ions are first impregnated from the aqueous solution on titania nanopowder and then, reduced by aqueous solution of sodium borohydride. The prepared Ru0/TiO 2 NPs are dried, bottled under inert N 2 gas atmosphere, and used for characterization by XRD (X-ray powder diffraction), TEM (transmission electron microscopy), ICP-OES (inductively coupled plasma optical emission spectroscopy) and XPS (X-ray photoelectron spectroscopy). Ru0/TiO 2 NPs with various Ru loadings are tested as catalysts in hydrogen generation from DMAB and the Ru0/TiO 2 (0.48% wt. Ru) with an average diameter of 6.7 ± 1.3 nm is found to have the highest initial turnover frequency value of 1700 h−1 for the release of 1.0 mol H 2 per mole of DMAB at 60 °C. Results of the recyclability test indicate quite high durability of Ru0/TiO 2 NPs in dehydrogenation of DMAB. [Display omitted] • Ru0/TiO 2 NPs are prepared by impregnation of Ru3+ ions on the surface of titania followed by their reduction. • Ru0/TiO 2 NPs show high catalytic performance in dehydrogenation of dimethylamine borane. • Ru0/TiO 2 (0.48% wt. Ru) provide a record TOF value of 1700 h−1 in this reaction at 60 °C. [ABSTRACT FROM AUTHOR]

Here, carbon quantum dot (CQD) supported Ru nanoparticles from the caffeine in methanol or water by the hydrothermal method were synthesized for the first time to produce hydrogen (H 2) by hydrolysis of ammonia borane(NH 3 BH 3) and their catalytic activities were investigated. The chemical compositions and morphology structures of this caffeine carbon dot-supported Ru catalysts were carefully characterized by UV, PL, TEM, FTIR, and ICP/OES analyses. Well-dispersed Ru nanoclusters with ∼1.81 nm particle size on CQD by the hydrothermal method in methanol medium showed very good catalytic performance. The turnover frequency (TOF) obtained for H 2 production from the catalytic hydrolysis of 5% NH 3 BH 3 with CQD supported Ru catalyst obtained by the hydrothermal method in methanol and water was found to be 361 and 1895 mol H 2 min−1 mol−1, respectively. The activation energies (Ea) for NH 3 BH 3 hydrolysis with the same catalysts were measured as 33.32 and 27.80 kJmol-1, respectively. [Display omitted] • CQD supported Ru nanoparticles in methanol or water by hydrothermal method were synthesized. • CQD supported Ru nanoparticles were used to produce H 2 by hydrolysis of NH 3 BH 3. • Ru@CQD(methanol) nanoclusters with 1.81 nm were prepared by hydrothermal method. • TOF value obtained by Ru@CQD(methanol) was 1895 min−1. • Ea for NH 3 BH 3 hydrolysis by Ru@CQD(methanol) was 27.80 kJmol-1. [ABSTRACT FROM AUTHOR]

The use of CO 2 -rich natural gas as feedstock in DRM is an attractive route of carbon dioxide utilisation due to the compositional advantage of these particular resources. The optimal operating conditions would potentially improve the overall thermal efficiency of the DRM process, especially when the temperature is lower than 800 °C. This study reports a catalyst with the demonstrated high performance and high coke-resistance, developed from ruthenium modified ceria-zirconia. Coprecipitation and hydrothermal methods were adopted to prepare the ceria-zirconia supports, and then impregnated with a very small amount of Ru (0.10 wt%). The structure-catalytic activity relationship of the catalyst was further investigated in DRM. High conversions of CH 4 and CO 2 , i.e., 44.0% and 57.4%, respectively, were achieved by using 0.1Ru1CZ5U-180 at low temperature of 600 °C. A significant reduction in the onset reaction temperature was observed from temperature programmed reduction (TPR) and this observation was related to the increased number of exchangeable oxygens in the presence of Ru. Nitrogen adsorption-desorption results suggested that the specific surface area and the total pore volume also improved the exchange of oxygen between adsorbed carbon dioxide molecules and the crystal lattice. It is evident that the presence of ruthenium accelerated the oxygen spillover process on the surface of the catalyst, and facilitated the dynamics of the oxygen exchange between the adsorbed carbon dioxide molecules and the ceria-zirconia, which ultimately contributed to the observed increase in catalytic activity at temperatures below 800 °C. Most importantly, no detectable carbon deposits were formed over the entire experimental period when the ruthenium modified ceria-zirconia catalyst was used. • A trace amount of Ru (0.10 wt%) was used to promote ceria-zirconia. • 0.10 wt% Ru significantly increased its reducibility and oxygen exchange dynamics. • Synthesis method showed a performance difference at temperatures between 400 and 850 °C. • 44% of CH 4 and 57.4% CO 2 were converted at 600 °C by 0.1Ru1CZ5U-180. • No observable carbon formation was detected from hydrothermally prepared samples. [ABSTRACT FROM AUTHOR]

A series of Co–Ce–Al–O mesoporous catalysts synthesised by self-assembly is shown to be efficient for the hydrogen production via ammonia decomposition reaction. The evaporation-induced self-assembly method is utilised to effectively synthesise mesoporous multicomponent catalysts with tuned composition and improved performance. The prepared catalyst materials were characterised by several techniques including X-ray diffraction, scanning electron microscope, transmission electron microscope and N 2 physisorption analysis. The kinetic performance of the solid catalysts was evaluated at different temperatures and flow rates under atmospheric pressure. The optimised Co 0.5 Ce 0.1 Al 0.4 O(sa) catalyst remained highly active below 550 °C which represents a competitive performance among state-of-the-art catalysts. The promising performance of the catalyst and the use of nonprecious metals in the structure represent a feasible approach towards the application of ammonia as a hydrogen carrier for on-board hydrogen production. [Display omitted] • The Co–Ce–Al–O mesoporous catalyst is prepared using a self-assembly method for ammonia decomposition. • Ammonia conversion of 98% was obtained at 550 °C with the GHSV of 12,000 mL h−1 g cat −1. • Cerium promoted the catalyst activity, and aluminium enhanced the catalyst stability. • The Co–Ce–Al–O catalytic performance is comparable to Ru-based catalysts. [ABSTRACT FROM AUTHOR]

The development of an effective molecular catalyst to reduce hydrazine efficiently to ammonia using a suitable reductant and proton source is demanding. Herein, an unprecedented air-stable, phosphine-free ruthenium complex is used as a potent catalyst for hydrazine hydrate reduction to generate ammonia using SmI2 and water under ambient reaction conditions. Maximizing the flow of electrons from the reductant to the hydrazine hydrate via the metal centre results in a greater yield of ammonia while minimizing the evolution of H2 gas as a competing product. [ABSTRACT FROM AUTHOR]

The selective semihydrogenation of C2H2 to C2H4 in crude C2H4 (with ~1 vol % C2H2 contamination) is a crucial process in the manufacture of polyethylene. Comparing to conventional thermalcatalytic route with Pd as catalyst under high temperature with H2 as hydrogen source, photocatalytic C2H2 reduction reaction with H2O as hydrogen source can achieve high selectivity under milder conditions, but has rarely been reported. Here, we present a kind of ultrathin metal–organic framework nanosheets (Cu‐Co‐MNSs) that demonstrate excellent catalytic activities in the semihydrogenation of C2H2. Employing Ru(bpy)32+ as the photosensitizer, this catalyst attains a noteworthy turnover number (TON) of 2124 for C2H4, coupled with an impressive selectivity of 99.5 % after 12 h visible light irradiation. This performance is comparable to molecular catalysts and notably surpasses the efficiency of bulk metal–organic framework materials. Furthermore, Cu‐Co‐MNSs achieve a 99.95 % conversion of C2H2 under industrial relevant conditions (1.10 % C2H2 in C2H4) with 90.3 % selectivity for C2H4 over C2H6, demonstrating a great potential for polymer‐grade C2H4 production. [ABSTRACT FROM AUTHOR]

The state-of-the-art alkaline hydrogen evolution catalyst of united ruthenium single atoms and small ruthenium nanoparticles has sparked considerable research interest. However, it remains a serious problem that hydrogen evolution primarily proceeds on the less active ruthenium single atoms instead of the more efficient small ruthenium nanoparticles in the catalyst, hence largely falling short of its full activity potential. Here, we report that by combining highly oxophilic cerium single atoms and fully-exposed ruthenium nanoclusters on a nitrogen functionalized carbon support, the alkaline hydrogen evolution centers are facilely reversed to the more active ruthenium nanoclusters driven by the strong oxophilicity of cerium, which significantly improves the hydrogen evolution activity of the catalyst with its mass activity up to −10.1 A mg−1 at −0.05 V. This finding is expected to shed new light on developing more efficient alkaline hydrogen evolution catalyst by rational regulation of the active centers for hydrogen evolution. The Ru single atom-nanocluster alkaline hydrogen evolution catalyst suffers from that hydrogen forms on its less active single atom side. Here, the authors report that oxophilic Ce single atom can reverse the hydrogen formation site to more active Ru nanocluster, enabling enhanced hydrogen evolution capabilities. [ABSTRACT FROM AUTHOR]

The three typical oxygen-containing functional groups on C-dots have been selectively deactivated to elucidate their impact on the co-reactant behavior of C-dots, and the carboxyl groups on C-dots are revealed for the first time as co-reactant sites for Ru(bpy) 3 2+-ECL. [Display omitted] Carbon nanodots (C-dots) with good biocompatibility have been extensively utilized as co-reactants for electrochemiluminescence (ECL) of the tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy) 3 2+) system. However, the ECL intensity of this system is still relatively low and the mechanism of C-dots as co-reactants remains unclear, which greatly limits its further application in bio-analysis. In this work, we revealed that the carboxyl groups on C-dots are co-reactant sites for Ru(bpy) 3 2+ ECL by systematically investigating the contribution of carboxyl, hydroxyl and carbonyl groups on the surface of C-dots to the ECL intensity. Further treatment with hydrogen peroxide to increase the carboxyl-group content on C-dots resulted in a 10-fold increase in ECL intensity over the original Ru(bpy) 3 2+/C-dots system. This work provides new insights for the rational design of ECL systems with C-dots as co-reactants and offers new chances for further applications of C-dots in the field of ECL. [ABSTRACT FROM AUTHOR]

The creation of affordable, long-lasting, and effective electrocatalysts is a significant research issue in the area of water splitting. In this work, Ru-modified CoP x spearhead on nickel foam (Ru-CoP x /NF) is fabricated by simple hydrothermal, impregnation and subsequent low-temperature phosphorization process. The incorporation of Ru into the Co-P structure enables the effective reconstruction of the electronic coordination environment. The Ru-CoP x /NF catalyst performs well for hydrogen evolution reaction (HER), achieving a current density of 10 mA cm−2 with low overpotentials of 41 mV and outstanding stability in 1 M KOH. Furthermore, the produced CoP x /NF has low overpotential of 280 mV, allowing 10 mA cm−2 for the oxygen evolution reaction (OER) in 1 M KOH. In addition, the developed asymmetric Ru-CoP x /NF||CoP x /NF electrolyzer could drive 10 mA cm−2 in alkaline electrolyte with a low cell voltage of 1.51 V. Surprisingly, water-splitting may be efficiently by renewable energy sources, presenting a viable strategy for lowering the cost of creating hydrogen energy. The synthesized Ru-CoP x /NF exhibits excellent electrocatalytic performance for HER, with low overpotentials of 41, 73 and 168 mV, driving 10 mA cm−2 in alkaline, acidic and neutral media, respectively. The synthesized CoP x /NF without Ru has excellent OER performance, with an overpotential of only 280 mV@10 mA cm−2. The Ru-CoP x /NF||CoP x /NF electrolyzer can be powered by sustainable energies. [Display omitted] • The spearhead-like nanostructures provide abundant active sites. • The introduction of Ru optimized the reaction kinetics for HER. • The prepared catalysts exhibit excellent catalytic performance for HER and OER. [ABSTRACT FROM AUTHOR]

Atomically precise Au nanoclusters (NCs) with discrete energy levels can be used as photosensitizers for CO2 reduction. However, tight ligand capping of Au NCs hinders CO2 adsorption on its active sites. Here, a new hybrid material is obtained by anchoring of thiol functionalized terpyridine metal complexes (metal=Ru, Ni, Fe, Co) on Au NCs by ligand exchange reactions (LERs). The anchoring of Ru and Ni complexes on Au25 NC (Au25−Ru and Au25−Ni) leads to adequate CO2 to CO conversion for photocoupled electrocatalytic CO2 reduction (PECR) in terms of high selectivity, with Faradaic efficiency of CO (FECO) exceeding 90 % in a wide potential range, remarkable activity (CO production rate up to two times higher than that for pristine Au25PET18) and extremely large turnover frequencies (TOFs, 63012 h−1 at −0.97 V for Au25−Ru and 69989 h−1 at −1.07 V vs. RHE for Au25−Ni). Moreover, PECR stability test indicates the excellent long‐term stability of the modified NCs in contrast with pristine Au NCs. The present approach offers a novel strategy to enhance PECR activity and selectivity, as well as to improve the stability of Au NCs under light illumination, which paves the way for highly active and stable Au NCs catalysts. [ABSTRACT FROM AUTHOR]

The integration of dual asymmetric catalysis is highly beneficial for the synthesis of organic molecules with multiple stereocenters. However, two major issues that need to be addressed are the intrinsic deactivation of dual-species and the extrinsic conflict of reaction conditions. To overcome these concerns, we have utilized the compartmental and thermoresponsive properties of poly(N-isopropylacrylamide) (PNIPAM) to develop a cross-linked PNIPAM-hydrogel-supported bifunctional catalyst. This catalyst is designed with Rh(diene) species situated on the outer surface and Ru(diamine) species positioned within the interior of the hydrogel. The compartmental function of PNIPAM in the middle overcomes intrinsic mutual deactivations between the dual-species. The thermoresponsive nature of PNIPAM allows for precise control of catalytic pathways in resolving external conflicts by controlling the reaction switching between an Rh-catalyzed enantioselective 1,4-addition at 50°C and a Ru-catalyzed asymmetric transfer hydrogenation (ATH) at 25°C. As we envisioned, this sequential 1,4-addition/reduction dual enantioselective cascade reaction achieves a transformation from incompatibility to compatibility, resulting in direct access to γ-substituted cyclic alcohols with dual stereocenters in high yields and enantio/diastereoselectivities. Mechanistic investigation reveals a reversible temperature transition between 50°C and 25°C, ensuring a cascade process comprising a 1,4-addition followed by the ATH process. Dual asymmetric catalysis is powerful for the synthesis of multi-stereocenter molecules, however, the integration of dual catalysts remains challenging due to the intrinsic deactivation of dual-species and extrinsic conflict of reaction conditions. Here, the authors develop a compartmental and thermoresponsive poly(N-isopropylacrylamide)-hydrogel-supported bifunctional catalyst to overcome these challenges. [ABSTRACT FROM AUTHOR]

Crystalline phase engineering is a prominent strategy for synergistically optimizing the surface–body phases of a catalyst. In this work, TiO2 nanosheets assembled into nanotubes (TNSTs) with two phases, anatase and rutile, were firstly synthesized via crystal engineering by simple thermal annealing. These were subsequently loaded with Ru nanoparticles, with a mean size of 5.0 nm, to create the efficient benzene hydrogenation catalyst Ru/TNSTs. The well-designed nanosheet-tube structure boasts a large specific surface area and excellent transmission channels, which effectively prevents the agglomeration and deactivation of loaded Ru nanoparticles, as well as promoting the internal diffusion in the reaction process of benzene hydrogenation to cyclohexene. Furthermore, titanium dioxide nanosheet-tubes contain numerous Ti3+ defects, which not only improves the overall conversion rate of cyclohexene but also enhances the suppression of cyclohexene adsorption. Most importantly, the titanium dioxide with its two-phase composition of 75 wt% anatase and 25 wt% rutile increases the ratio of electron deficiencies of Ru and promotes cyclohexene desorption. These synergistic properties enhance the selectivity and efficiency of the Ru/TNSTs catalysts, resulting in excellent performance in the hydrogenation of benzene to cyclohexene. In particular, the Ru/TNSTs-4 catalyst (annealed for 4 h), under the specific conditions of 140 °C temperature and 5 MPa hydrogen pressure for the hydrogenation process, achieves a 95% initial selectivity and 51% yield of cyclohexene in the reaction, outperforming most supported Ru-based catalysts. This work may provide new perspectives for designing efficient benzene hydrogenation catalysts via crystalline phase engineering. [ABSTRACT FROM AUTHOR]

Cobalt-iron bimetallic catalysts promoted with Nb, Ru or Rh and supported on multiwalled-carbon nanotubes (MWCNTs) were synthesized using a reverse-microemulsion method. The synthesized catalysts were characterized by TEM, N2-physical adsorption, XPS, XRD, and TPD/R/O methods. XPS analyses showed an increasing trend of the Co2+/Co3+ atomic ratios for the promoted catalysts, compared to that of the un-promoted Co–Fe/CNTs catalyst. The dispersion for the un-promoted Co–Fe /CNTs catalyst was 15.9% and it increased to 23.0, 20.4, and 17.7% in the presence of 0.1 wt.% Nb, Ru, and Rh promoter, respectively. The addition of Nb-promoter also improved the reducibility of the catalyst as exhibited by the H2-TPR study. The presence of Nb, Ru, and Rh promoters improved the catalytic performance in a Fischer–Tropsch synthesis where the TOF over the un-promoted catalyst increased from 5.1 to 6.2, 5.7, 5.2 × 10–1 s−1 upon the addition of Nb, Ru and Rh promoter, respectively. Thus, the Nb promoter was a better promoter than Ru and Rh for the Co–Fe/CNTs catalyst. [ABSTRACT FROM AUTHOR]

The structure and electrocatalytic activity of the Ru-doped cobalt oxides derived from the metal–organic frameworks (MOFs) for large-current–density water splitting are highly dependent on the preorganized structure and chemistry of the MOFs. [Display omitted] The influence of the preorganized structure and chemical composition of metal-organic frameworks (MOFs) on the morphology, surface properties, and catalytic activity of the MOFs-derived metal oxides is yet to be revealed. In this work, two types of Co-MOFs with different coordination configurations are synthesized for the preparation of the structure-engineered ruthenium (Ru)-doped cobalt oxides. The effect of the preorganized coordination structure of the MOFs on the morphology and surface properties is investigated. Interestingly, the oxalate-based MOFs derived Ru-doped cobalt oxide (OX-Co 3 O 4 -Ru) exhibits much better surface wettability and more oxygen vacancies than the zeolitic imidazolate framework-67 derived Ru-doped cobalt oxide. As expected, the OX-Co 3 O 4 -Ru owns excellent catalytic properties towards both hydrogen evolution reaction and oxygen evolution reaction with an overpotential of 49 and 286 mV, respectively at a current density of 100 mA cm−2 in 1.0 M KOH. Importantly, the bifunctional OX-Co 3 O 4 -Ru catalyst offers an extremely high current density of 500 mA cm−2 at a cell voltage of 1.71 V for overall water splitting and as well demonstrates robust working stability. [ABSTRACT FROM AUTHOR]

The title compound, [RuCl2(C33H43N3O)], is an example of a new generation of N,N-dialkyl ruthenium catalysts with an N--Ru coordination bond as part of a six-membered chelate ring. The Ru atom has an Addison parameter of 0.244, which indicates a geometry intermediate between square-based pyramidal and trigonal-bipyramidal. The complex shows the usual trans arrangement of the two chlorides, with Ru--Cl bond lengths of 2.3515 (8) and 2.379 (7) Å, and a Cl--Ru--Cl angle of 158.02 (3)°. One of the chlorine atoms and the atoms of the 2-methoxy-N-methyl-N-[(2-methylphenyl)methyl]ethane-1-amine group of the title complex display disorder over two positions in a 0.889 (2): 0.111 (2) ratio. [ABSTRACT FROM AUTHOR]

Ar, Ar/H2 (95:5), and Ar/O2 (95:5) plasmas are used for treating the NiCo metal–organic framework (MOF), and the plasma-processed NiCo MOF is applied for catalyzing the oxygen evolution reaction (OER) in a 1 M KOH electrolyte. Linear sweep voltammetry measurements show that after plasma treatment with Ar/H2 (95:5) and Ar gases, the overpotential reaches 552 and 540 mV, respectively, at a current density of 100 mA/cm2. The increase in the double-layer capacitance further confirms the enhanced oxygen production activity. We test the Ar plasma-treated NiCo MOF as an electrocatalyst at the OER electrode and Ru as an electrocatalyst at the hydrogen evolution reaction (HER) electrode in the alkaline water electrolysis module. The energy efficiency of the electrolyzer with the Ar plasma-processed NiCo-MOF catalyst increases from 54.7% to 62.5% at a current density of 500 mA/cm2 at 25 °C. The alkaline water electrolysis module with the Ar plasma-processed catalyst also exhibits a specific energy consumption of 5.20 kWh/m3 and 4.69 kWh/m3 at 25 °C and 70 °C, respectively. The alkaline water electrolysis module performance parameters such as the hydrogen production rate, specific energy consumption, and energy efficiency are characterized at temperatures between 25 °C and 70 °C. Our experimental results show that the NiCo MOF is an efficient OER electrocatalyst for the alkaline water electrolysis module. [ABSTRACT FROM AUTHOR]

Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO2 reduction to solar fuels. A surface‐modified Ag@Ru‐P25 photocatalyst with H2O2 treatment was designed in this study to convert CO2 and H2O vapor into highly selective CH4. Ru doping followed by Ag nanoparticles (NPs) cocatalyst deposition on P25 (TiO2) enhances visible light absorption and charge separation, whereas H2O2 treatment modifies the surface of the photocatalyst with hydroxyl (–OH) groups and promotes CO2 adsorption. High‐resonance transmission electron microscopy, X‐ray photoelectron spectroscopy, X‐ray absorption near‐edge structure, and extended X‐ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst, while thermogravimetric analysis, CO2 adsorption isotherm, and temperature programmed desorption study were performed to examine the significance of H2O2 treatment in increasing CO2 reduction activity. The optimized Ag1.0@Ru1.0‐P25 photocatalyst performed excellent CO2 reduction activity into CO, CH4, and C2H6 with a ~95% selectivity of CH4, where the activity was ~135 times higher than that of pristine TiO2 (P25). For the first time, this work explored the effect of H2O2 treatment on the photocatalyst that dramatically increases CO2 reduction activity. [ABSTRACT FROM AUTHOR]

Xylose is nowadays converted into xylitol, a popular special chemical sweetener. Xylitol can be used not only in the pharmaceutical and food industries, but also in cosmetics and synthetic resins because of its countless properties. Conventionally, xylitol is produced by slurry reactors operating in batch with dispersed or supported catalysts. Hydrogen is continuously fed to maintain a constant pressure. In this work, the kinetics of the reaction were investigated to find the optimal operating conditions to minimize the by-products obtained. Given the great performances shown by the new Ru/SiO2 sol–gel derived catalyst in glucose hydrogenation, in this work the mentioned catalyst was tested in the hydrogenation of xylose to xylitol both in batch and in continuous production to prove its stability and activity. [ABSTRACT FROM AUTHOR]

This study introduces an efficient strategy for promoting the synthesis of γ-valerolactone (GVL) via levulinic acid (LA) hydrogenation. A series of hyper-crosslinked porous polymer (HCP) supported Ru catalysts with different monomers were prepared. The wettabilities were controlled by the surface functional groups. The hydrophobic catalysts showed much higher activity than the hydrophilic ones in the hydrogenation of LA to GVL, highly possible due to the substrate enrichment. Further insight showed that the reaction proceeded through the 4-HVA route. These results illustrated the importance of surface wettability in bio-based molecule upgrading, which is beneficial for catalyst design. [ABSTRACT FROM AUTHOR]

Nature uses reactive components embedded in biological membranes to perform light‐driven photosynthesis. Here, a model artificial photosynthetic system for light‐driven hydrogen (H2) evolution is reported. The system is based on liposomes where amphiphilic ruthenium trisbipyridine based photosensitizer (RuC9) and the H2 evolution reaction (HER) catalyst [Mo3S13]2− are embedded in biomimetic phospholipid membranes. When DMPC was used as the main lipid of these light‐active liposomes, increased catalytic activity (TONCAT ~200) was observed compared to purely aqueous conditions. Although all tested lipid matrixes, including DMPC, DOPG, DPPC and DOPG liposomes provided similar liposomal structures according to TEM analysis, only DMPC yielded high H2 amounts. In situ scanning electrochemical microscopy (SECM) measurements using Pd microsensors revealed an induction period of around 26 minutes prior to H2 evolution, indicating an activation mechanism which might be induced by the fluid‐gel phase transition of DMPC at room temperature. Stern‐Volmer‐type quenching studies revealed that electron transfer dynamics from the excited state photosensitizer are most efficient in the DMPC lipid environment giving insight for design of artificial photosynthetic systems using lipid bilayer membranes. [ABSTRACT FROM AUTHOR]

Developing cost‐efficient bifunctional water splitting catalysts is crucial for sustainable hydrogen energy applications. Herein, ruthenium (Ru)‐incorporated and phosphorus (P)‐doped nickel molybdate (Ru‐NiMoO(P)4) nanosheet array catalysts are synthesized. Due to the synergy of Ru clusters and NiMoO(P)4 by the modulated electronic structure and the rich active sites, impressively, Ru‐NiMoO(P)4 exhibits superior OER (194 mV @ 50 mA cm−2) and HER (24 mV @ 10 mA cm−2) activity in alkaline media, far exceeding that of commercial Pt/C and RuO2 catalysts. Meanwhile, as bifunctional catalyst, to drive the overall water splitting at the current density of 10 mA cm−2, Ru‐NiMoO(P)4 requires only 1.45 V and maintaining stable output for 100 h. Furthermore, Ru‐NiMoO(P)4 also possesses excellent capability for seawater electrolysis hydrogen production. Moreover, the successful demonstration of wind and solar hydrogen production systems provide the feasibility of the ultra‐low Ru loading catalyst for large‐scale hydrogen production in the future. [ABSTRACT FROM AUTHOR]

By rationally adjusting the coordination environment and constructing the more electron‐enriched active site in single‐atom catalysts, the effect of heterogenous peroxymonosulfate (PMS)‐based Fenton‐like reactions can be effectively improved, yet remains a severe challenge. In this study, the electron‐rich Ru dual‐atom site is successfully immobilized onto N‐doped carbon (Ru2N6‐C) for PMS activation in water purification. The presence of electron‐rich Ru dual‐atom sites not only provides more electrons for PMS but also facilitates the formation of a Yeager adsorption configuration on the catalyst surface, which enhances O─O bond cleavage and leads to an increase in •SO4− and •OH generation. Moreover, the Ru2N6‐C catalyst exhibits exceptional durability and reliability, achieving an ultra‐high efficiency with a turnover frequency of 153.95 min−1 M−1 for the naproxen degradation. A membrane reactor is further developed for the purification of wastewater, which is expected to provide a viable approach to controlling water pollution through the design of metal dual‐atom sites carbon‐based catalysts. [ABSTRACT FROM AUTHOR]

The thermal treatment is one of the key procedures for the distribution and transformation of active sites for the supported metal oxide catalysts. However, the underlying impacts of thermal treatment on composite supported catalysts receives limited attention due to the additional complexity of the composite support. In this work, the progressive gradient in the metathesis activity, as the function of enhanced calcination temperature, has been observed for the tungsten‐based catalysts supported on the hierarchical ZSM‐5 zeolite‐alumina composite. The metathesis activity, reflected by ethene conversion, undergoes a stepwise growth from 24.2 % to 38.9 % along with the enhanced calcination temperature from 723 K to 923 K. The supported W‐oxo species share high similarity in structural states except their interaction with the Brønsted acidic bridge hydroxyl groups in zeolite. The density of bridge hydroxyl groups is reduced as the function of enhanced calcination temperatures, which reflects the intensified anchoring of surface W‐oxo species. It should be noted that such dependence is not observed for their counterparts based on microporous ZSM‐5 zeolite‐alumina. These sharp comparisons highlight the critical routes of thermal migration of W‐oxo species along the intrazeolite‐alumina interface in the evolution of active sites for the olefins cross‐metathesis reaction. [ABSTRACT FROM AUTHOR]

The development of catalytic systems for the oxidation of organic substrates using renewable sources such as water and dioxygen remains challenging. In this paper we report the synthesis and full characterization of a new dyad combining a ruthenium(II)‐based chromophore and a bio‐inspired copper(II) pre‐catalyst. In particular, photo‐induced electron transfer from the photosensitized RuII subunit toward the CuII center is highlighted. The photogenerated CuI moiety proves to be catalytically efficient for sulfides oxidation by 3O2 in the presence of a sacrificial electron source. Finally, the covalent association of the two partners favors Cu/O2‐based catalysis at the expense of a 1O2‐centered reactivity for a bimolecular mixture. [ABSTRACT FROM AUTHOR]

The efficient decomposition of ammonia to produce COx‐free hydrogen at low temperatures has been extensively investigated as a potential method for supplying hydrogen to mobile devices based on fuel cells. In this study, we employed dielectric barrier discharge (DBD) plasma, a non‐thermal plasma, to enhance the catalytic ammonia decomposition over supported Ru catalysts (Ru/Y2O3, Ru/La2O3, Ru/CeO2 and Ru/SiO2). The plasma‐catalytic reactivity of Ru/La2O3 was found to be superior to that of the other three catalysts. It was observed that both the physicochemical properties of the catalyst (such as support acidity) and the plasma discharge behaviours exerted significant influence on plasma‐catalytic reactivity. Combining plasma with a Ru catalyst significantly enhanced ammonia conversion at low temperatures, achieving near complete NH3 conversion over the 1.5 %‐Ru/La2O3 catalyst at temperatures as low as 380 °C. Under a weight gas hourly space velocity of 2400 mL gcat−1 h−1 and an AC supply power of 20 W, the H2 formation rate and energy efficiency achieved were 10.7 mol gRu−1 h−1 and 535 mol gRu−1 (kWh)−1, respectively, using a 1.5 %‐Ru/La2O3 catalyst. [ABSTRACT FROM AUTHOR]

The in-situ activation process alleviates the strong ruthenium-hydrogen and ruthenium-hydroxyl bonds, optimizing hydrogen and hydroxyl desorption energy. [Display omitted] • Partially oxidized Ru nanoparticles dispersed Ni 3 N nanosheet electrocatalyst was developed. • The in-situ electrochemical activation effectively promoted hydrogen evolution. • The controlled oxidation alleviates the strong Ru-H and Ru-OH bonds. • The catalysts show superior performance for HER and urea-assisted water splitting. The rational design of electrocatalysts with exceptional performance and durability for hydrogen production in alkaline medium is a formidable challenge. In this study, we have developed in-situ activated ruthenium nanoparticles dispersed on Ni 3 N nanosheets, forming a bifunctional electrocatalyst for hydrogen evolution and urea oxidation. The results of experimental analysis and theoretical calculations reveal that the enhanced hydrogen evolution reaction (HER) performance of O-Ru-Ni 3 N stems primarily from the optimized hydrogen adsorption and hydroxyl adsorption on Ru sites. The O-Ru-Ni 3 N on nickel foam (NF) electrode exhibits excellent HER performance, requiring only 29 mV to reach 10 mA cm−2 in an alkaline medium. Notably, when this O-Ru-Ni 3 N/NF catalyst is employed for both HER and urea oxidation reaction (UOR) to create an integrated H 2 production system, a current density of 50 mA cm−2 can be generated at the cell voltage of 1.41 V. This report introduces an energy-efficient catalyst for hydrogen production and proposes a viable strategy for anodic activation in energy chemistry. [ABSTRACT FROM AUTHOR]

PROteolysis TArgeting Chimeras (PROTACs) are heterobifunctional molecules emerging as a powerful modality in drug discovery, with the potential to address outstanding medical challenges. However, the synthetic feasibility of PROTACs, and the empiric and complex nature of their structure-activity relationships continue to present formidable limitations. As such, modular and reliable approaches to streamline the synthesis of these derivatives are highly desirable. Here, we describe a robust ruthenium-catalysed late-stage C‒H amidation strategy, to access fully elaborated heterobifunctional compounds. Using readily available dioxazolone reagents, a broad range of inherently present functional groups can guide the C–H amidation on complex bioactive molecules. High selectivity and functional group tolerance enable the late-stage installation of linkers bearing orthogonal functional handles for downstream elaboration. Finally, the single-step synthesis of both CRBN and biotin conjugates is demonstrated, showcasing the potential of this methodology to provide efficient and sustainable access to advanced therapeutics and chemical biology tools. PROTACs are uniquely powerful therapeutic agents, but their synthetic tractability significantly limit drug discovery programs. Here, the authors developed a single step synthesis of PROTAC conjugates via late stage ruthenium-catalysed C–H amidation. [ABSTRACT FROM AUTHOR]

The catalytic alkoxycarbonylation of alkenes is an attractive, atom‐efficient method for producing value‐added carboxylic esters. However, the conventional catalyst system for this reaction needs coordination with a noble metal, sensitive ligands and proton acid additives. Therefore, the design of a simple and efficient catalyst system without any acid additives under mild conditions is still a major challenge. In this work, a simple ruthenium/deep eutectic solvent catalytic system was developed to effectively catalyse the alkoxycarbonylation reaction without any sensitive ligands or acid additives under mild conditions. The conversion of 1‐hexene reached 99.0 %, and the ester selectivity was 99.1 %, much higher than that of Ruthenium carbonyl without deep eutectic solvent. The excellent performance of the catalytic system could be ascribed to the form of the ruthenium active species [Ru(CO)2Br3]− in the deep eutectic solvent. This innovative catalyst system presents a significant advancement in the alkoxycarbonylation reaction, eliminating the use of acid additives and delicate ligands. [ABSTRACT FROM AUTHOR]