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The contribution of atomic nitrogen is fairly possible in plasma-assisted catalytic synthesis of ammonia since it has high adsorption probabilities on solid surfaces. On the other hand, recently, the contribution of vibrational excited molecular nitrogen to ammonia synthesis has been discussed. In this work, we compared the fluxes of atomic nitrogen and vibrational excited molecular nitrogen with the rate of plasma-assisted ammonia synthesis. We employed an atmospheric-pressure nitrogen plasma jet, and the spatial afterglow of the plasma jet and a hydrogen flow irradiated the surface of a ruthenium catalyst. The fluxes of atomic nitrogen and vibrational excited molecular nitrogen were measured by two-photon absorption laser-induced fluorescence spectroscopy and laser Raman scattering, respectively. The synthesis rate of ammonia had a positive correlation with the flux of vibrational excited molecular nitrogen, while the variation of the synthesis rate with the gas flow rate was opposite to the flux of atomic nitrogen. The experimental results indicate the contribution of vibrational excited molecular nitrogen to the synthesis of ammonia using the atmospheric-pressure plasma, where the flux of vibrational excited molecular nitrogen is more than four orders of magnitude higher than that of atomic nitrogen. [ABSTRACT FROM AUTHOR]

Two new supramolecular photocatalysts made of covalently linked Ru(II) polypyridine chromophore subunits ([Ru(bpy)3]2+-type species; bpy = 2,2′-bipyridine) and [RuL(pic)2] (L = 2,2′-bipyridine-6,6′-dicarboxylic acid; pic = 4-picoline) water oxidation catalyst subunits have been prepared. The new species, 1 and 2, contain chromophore and catalyst subunits in the molecular ratios 1:1 and 1:2, respectively. The model chromophore species [Ru(bpy)2(L1)]2+ (RuP1; L1=4-[2-(4-pyridyl)-2-hydroxyethyl]-4-methyl-2,2′-bipyridine) and [Ru(bpy)2(L2)]2+ (RuP2; L2 = 4,4′-bis[2-(4-pyridyl)-2-hydroxyethyl]-2,2′-bipyridine) have also been prepared. The absorption spectra, oxidation behavior, and luminescent properties of 1 and 2 have been studied, and the results indicate that each subunit largely maintains its own properties in the supramolecular species. However, the luminescence of the chromophore subunits is significantly quenched in 1 and 2 in comparison with the luminescence of the respective model species. Both 1 and 2 exhibit catalytic water oxidation in the presence of cerium ammonium nitrate, exhibiting an I2M mechanism, with a better efficiency than the known catalyst [RuL(pic)2] under the same experimental conditions. Upon light irradiation, in the presence of persulfate as a sacrificial acceptor agent, 1 and 2 are more efficient photocatalysts than a system made of separated [Ru(bpy)3]2+ and [RuL(pic)2] species, highlighting the advantage of using multicomponent, supramolecular species with respect to isolated species. The O–O bond formation step is I2M, even in the photo-driven process. The photocatalytic process of 2 is more efficient than that of 1, with the turnover frequency reaching a value of 1.2 s−1. A possible reason could be an increased local concentration of catalytic subunits in the needed bimolecular assembly required for the I2M mechanism in 2 with respect to 1, a consequence of the presence of two catalytic subunits in each multicomponent species 2. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of biomass-derived chemicals is essential in chemical industry due to the growing demand for sustainable and renewable energy sources. In this study, we present a comprehensive theoretical investigation regarding the hydrogenation of glycolaldehyde to ethylene glycol over a Ru/C catalyst by employing density functional theory and ab initio molecular dynamics simulations. With inclusion of explicit solvation, we have demonstrated that the glycolaldehyde hydrogenation is significantly improved due to the fast proton transfer through the hydrogen bond network. The enhanced activity could be attributed to the participation of the solvent water as the hydrogen source and the highly positively charged state of a Ru cluster in an aqueous phase, which are critical for the activation of aldehyde groups and proton-assisted hydrogenation. Overall, our findings provide valuable insights into glycolaldehyde hydrogenation over Ru/C catalysts in the aqueous phase, highlighting the importance of solvation effects in the biomass conversion. [ABSTRACT FROM AUTHOR]

Ru/HAP catalyst with high-dispersion is prepared by a novel homogeneous deposition precipitation method (DPU). As compared to the conventional impregnation method (IM), the catalytic oxidation performance for toluene and DCM are much higher for DPU-sample with higher activity and good stability in humid air. Characterizations reveal that DPU-sample has a larger surface area with mesoporous structure, keeping smaller Ru particle size and uniform distribution on HAP, which is favorable for the exposure of active sites. The preparation and reaction conditions were also systematically studied, showing that 0.5 Ru/HAP(500)-DPU sample is a promising catalyst for VOC and CVOC removal. The Ru/HAP (DPU) is a promising broad-spectrum catalyst for VOC and CVOC removal. [ABSTRACT FROM AUTHOR]

[Display omitted] Catalysts composed of nanocluster and single-atom (SA) were extensively used to enhance electrocatalytic water splitting performance, whereas study of their photocatalytic hydrogen (H 2) evolution activity was limited. Herein, carbon nitride (CN) decorated by ruthenium (Ru) cocatalysts existed as SA + cluster, cluster + nanoparticles (NPs), and NPs were prepared by impregnation and calcination processes. The correlation between existential form, content of Ru cocatalyst and H 2 evolution rate were carefully discussed. It was found that Ru NPs were favor for water molecule adsorption, whereas Ru SAs and clusters facilitated H 2 desorption. Theoretical calculations revealed that Ru clusters + NPs cocatalyst were beneficial for H* intermediate formation. Water splitting tests found that 1.07 wt% Ru NPs + cluster modified CN showed the highest H 2 evolution rate of 13.64 mmol h−1 g−1, which was 266.4 and 1.5 times higher than those of CN and Ru NPs (2.33 wt%) decorated CN, respectively. This work deeply reveals the influences of existential form of Ru cocatalysts on photocatalytic water splitting of CN, and provides thought in designing new cocatalysts to largely enhance H 2 evolution. [ABSTRACT FROM AUTHOR]

The development of cost‐effective, highly efficient, and durable electrocatalysts has been a paramount pursuit for advancing the hydrogen evolution reaction (HER). Herein, a simplified synthesis protocol was designed to achieve a self‐standing electrode, composed of activated carbon paper embedded with Ru single‐atom catalysts and Ru nanoclusters (ACP/RuSAC+C) via acid activation, immersion, and high‐temperature pyrolysis. Ab initio molecular dynamics (AIMD) calculations are employed to gain a more profound understanding of the impact of acid activation on carbon paper. Furthermore, the coexistence states of the Ru atoms are confirmed via aberration‐corrected scanning transmission electron microscopy (AC‐STEM), X‐ray photoelectron spectroscopy (XPS), and X‐ray absorption spectroscopy (XAS). Experimental measurements and theoretical calculations reveal that introducing a Ru single‐atom site adjacent to the Ru nanoclusters induces a synergistic effect, tuning the electronic structure and thereby significantly enhancing their catalytic performance. Notably, the ACP/RuSAC+C exhibits a remarkable turnover frequency (TOF) of 18 s−1 and an exceptional mass activity (MA) of 2.2 A mg−1, surpassing the performance of conventional Pt electrodes. The self‐standing electrode, featuring harmoniously coexisting Ru states, stands out as a prospective choice for advancing HER catalysts, enhancing energy efficiency, productivity, and selectivity. [ABSTRACT FROM AUTHOR]

The efficient preparation of long-chain amines via a one-step transfer-hydrogenation/reductive-amination reaction (THRA) of polyenals has been achieved. This strategy, which combines transfer hydrogenation and reductive amination, significantly enhances the synthetic efficiency of amino compounds. Additionally, this protocol offers a practical method for carbon-chain elongation/amination to construct long-chain amino compounds. The reaction system exhibits remarkable versatility in substrate scope using a non-noble ruthenium catalyst with formate and isopropanol as hydrogen sources, making it an appealing method for drug synthesis and molecular modification. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry," published by The Royal Society of Chemistry. It includes various articles on topics such as NHC aluminum chemistry, catalytic functionalization of ferrocenes, and energetic coordination polymers. The journal covers a wide range of research on inorganic chemistry, showcasing recent advances and studies in the field. [Extracted from the article]

Uniform and minuscule Ru particles confined in NaY zeolite (Ru@NaY) are prepared via a simple in situ synthesis technique. Transmission electron microscopy studies indicate that the Ru particles are encapsulated within the micropores of NaY zeolite and form a uniform size of 1.5–3.5 nm. Thanks to the effective confinement of Ru particles within the NaY zeolite, as well as the high concentration of B-5 sites and basic sites, the prepared Ru@NaY catalysts show excellent NH 3 decomposition activity and highly efficient H 2 formation. Notably, the 0.1Ru@NaY catalyst achieves a 92.7% NH 3 conversion and a H 2 formation rate of 690 mmol min−1·g Ru −1 at 500 °C and GHSV = 9000 mLNH 3 ·g cat −1·h−1 and shows outstanding stability throughout a 95-h lifetime test. The encapsulation synthesis of Ru clusters in zeolites endows the catalysts with exceptional catalytic activities and excellent stability, thus providing new prospects for the production of H 2 from NH 3 decomposition. [Display omitted] • Ru particles confined within NaY zeolite were prepared via hydrothermal synthesis. • Ru nanoparticles are uniformly sized, highly distributed, and thermally stable. • Ru@NaY catalysts showed high activity and stability for ammonia decomposition. • High level B-5 sites and basic sites accounts for the superior activity of Ru@NaY. [ABSTRACT FROM AUTHOR]

The development of efficient and durable bifunctional electrocatalysts is essential for hydrogen production from acidic water splitting. Herein, a TiO2 nanotube‐loaded Co‐doped Ru nanoparticle catalyst (RuCo/TiO2 NTs) is reported that exhibits excellent activity and stability toward acidic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The Ru─O─Ti bonding is enhanced by Co doping, and the metal carrier interaction between Ru nanoparticles and TiO2 NTs is enhanced, which effectively stabilizes Ru species during OER and initiates hydrogen spillover accelerating HER kinetics. As a result, RuCo/TiO2 NTs catalyst requires only 156 mV OER overpotential and 17 mV HER overpotential to achieve a current density of 10 mA cm−2 with a stability more than 500 h in acidic conditions. More importantly, benefiting from the excellent bifunctional activities, the proton exchange membrane electrolyte assembled from RuCo/TiO2 NTs has excellent activity and robust stability (1000 h). This work opens a new avenue for the efficient energy conversion devices. [ABSTRACT FROM AUTHOR]

The rational design of single atom‐based catalysts and precise elucidation of the synergistic interaction between the metal site and substrate are pivotal to identifying the real active sites and explicating the catalytic mechanisms at the atomic scale, thus contributing to the development of high‐performance catalysts for diverse industrial implementations. Herein, a Ru single‐atom doping strategy is developed to activate the MoC substrate with superior hydrogen evolution reaction (HER) activity in an alkaline medium. The atomically dispersed Ru sites are elaborately doped into MoC nanoparticles loaded on 3D N‐doped carbon nanoflowers (Ru‐SAs@MoC/NCFs hereafter). The experimental results and theoretical calculations manifest that the atomically isolated Ru dopants can effectively trigger the Mo sites with thermodynamically favorable water adsorption/dissociation energies and facilitate the OH− desorption on Ru sites and H adsorption on N sites, thus synergistically expediating the overall alkaline HER kinetics. As such, the well‐designed Ru‐SAs@MoC/NCFs demonstrate extraordinary HER activity with a low overpotential of 16 mV at 10 mA cm−2 in 1.0 m KOH electrolyte, outperforming Pt/C benchmark and a vast of molybdenum/ruthenium‐based HER catalysts reported to date. These findings disclose the alkaline HER mechanistic induced by the atomic doping modulation and suggest a design principle of high‐efficiency electrocatalysts via the atomic‐level manipulation leverage. [ABSTRACT FROM AUTHOR]

The document is a contents list for the New Journal of Chemistry. It includes information about the journal's mission and the Royal Society of Chemistry, as well as a list of papers and articles featured in the current issue. The topics covered in the papers range from dendrimer-stabilized silver nanoparticle platforms to the synthesis of sulfated lactosyl glycosides. The journal aims to connect the world with the chemical sciences and is published by the Royal Society of Chemistry and the Centre National de la Recherche Scientifique. [Extracted from the article]

Following our recent strategy of using suitably substituted ligand precursors for the synthesis of Ru(II)–CNC pincer complexes [Ru(CHNCMe)(PPh3)2Cl]Cl (1 and 2) with mixed protic- and classical-NHCs in the same molecule, synthesis of new phosphine-free complexes [Ru(CHNCMe)(CNMe)I]PF6 (3), [Ru(CHNCMe)(CNi-Pr)I]PF6 (4), [Ru(CHNCAd)(CNMe)I]PF6 (5), and [Ru(CHNCAd)(CNi-Pr)I]PF6 (6) has been achieved starting from our in-house made Ru(III)–NHC complexes [Ru(CNR′)(H2O)(Cl)3] (R′ = Me (P1), i-Pr (P2)) as precursors. This is the first report of phosphine-free Ru-complexes having mixed, protic- and classical-NHC within the same pincer ligand platform. We also note that this synthetic strategy gives racemic mixtures of chiral-at-the-metal complexes from nonchiral precursors. All new complexes have been characterized as racemic mixtures using multinuclear NMR (1H, 31P{1H}, 13C{1H} NMR) and high-resolution mass spectrometry (HRMS). The molecular structure of the racemic complex 6 has been determined by single-crystal X-ray diffraction and was found to contain both enantiomers in the same lattice. The catalytic activity of these complexes for oxidant-free, acceptorless dehydrogenation of benzyl alcohols to benzoic acids has been explored, revealing superior activity of complex 4 among the new complexes. Catalyst 4 was then screened for a wide range of substrates, including aliphatic, aromatic, and heteroaromatic benzyl alcohols, to give their corresponding carboxylic acids. Mechanistic investigations help identify some crucial intermediates during the catalytic reaction, and a plausible mechanism has been proposed. A maximum TON of 20 000 has been observed, greater than several previously reported ruthenium catalysts. [ABSTRACT FROM AUTHOR]

The Z-alkene geometry is prevalent in various chemical compounds, including numerous building blocks, fine chemicals, and natural products. Unfortunately, established Mo, W, and Ru Z-selective catalysts lose their selectivity at high temperatures required for industrial processes like reactive distillation, which limits their synthetic applications. To address this issue, we develop a catalyst capable of providing Z-alkenes with high selectivity under harsh conditions. Our research reveals a dithiolate ligand that, stabilised by resonance, delivers high selectivity at temperatures up to 150 °C in concentrated mixtures. This distinguishes the dithioquinoxaline complex from existing Z-selective catalysts. Notably, this trait does not compromise the new catalyst's usability under classical conditions, matching the activity of known stereoretentive catalysts. Density Functional Theory calculations were employed to understand the reaction mechanism and selectivity, and to investigate the poisoning that the catalyst may undergo and how it competes with catalytic activity. Furthermore, the quinoxaline-based catalyst enables the valorisation of bio-sourced alkene feedstocks and the production of agricultural sex pheromones for pest control. The Z-alkene geometry is prevalent in various chemical compounds, but established Mo, W, and Ru Z-selective catalysts lose their selectivity at high temperatures, which limits their synthetic applications. Here, the authors develop a catalyst capable of providing Z-alkenes with high selectivity under harsh conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Treatment of Ru3(CO)12 with salicylaldimine ligands [ArNCH(3‐tBuC6H3OH) [ArC6H5 (L1H); 4‐OMeC6H4 (L2H); 4‐MeC6H4 (L3H); 2,4,6‐Me3C6H2 (L4H); 4‐ClC6H4 (L5H); 4‐BrC6H4 (L6H)] in refluxing toluene afforded six bis‐ligand mononuclear ruthenium carbonyl complexes [ArNCH(3‐tBuC6H3O)]2Ru(CO)2 1a–1f in good yields. All of the Ru(II) complexes were characterized using IR, NMR, and elemental analysis. The molecular structures of complexes 1a, 1b, 1e, and 1f were further confirmed through X‐ray diffraction analysis. Additionally, the catalytic performance of these complexes was investigated in the oxidation of olefins to aldehydes, using TBHP as the oxidant in refluxing trichloromethane. With 1.0 mol% catalyst loading, these ruthenium complexes displayed high reactivity and good functional‐group compatibility, selectivity providing the corresponding oxidation product aldehydes in 73%–94% yields. [ABSTRACT FROM AUTHOR]

This study proposes a novel one‐pot method to produce 2,5‐furandicarboxylic acid (FDCA), which effectively simplifies the preparation process of FDCA by directly utilizing the biomass raw material corncob and its derived carbon‐based catalysts. In this work, we first prepared two different carbon‐based catalysts from corncobs: a ruthenium‐supported catalyst (Ru/C) and a sulfonated carbon catalyst. After detailed characterization and performance testing, these two catalysts were used to catalyze the pretreated corncob mixture to produce FDCA. Under optimized conditions, even using 0.12 g of Ru/C catalyst at a microwave power of 200 W, the yield of FDCA can reach 27 mol%. In comparison, the FDCA yield of the sulfonated carbon catalyst under the same conditions was 19 mol%. This work not only demonstrates the possibility of efficient production of FDCA by utilizing biomass resources and a simplified chemical conversion process, but also highlights the importance of selecting appropriate catalysts and controlling reaction conditions in improving yields. Through this method, we can promote the development of biomass conversion technology in a more efficient and environmentally friendly direction, providing technical support for the commercial production of bio‐based chemicals. [ABSTRACT FROM AUTHOR]

Ruthenium-based nanomaterials are considered to be promising electrocatalysts for HER due to their higher activity. However, the active site exposure is low, and the catalytic mass activity is low. In order to achieve the particular aims, several types of engineering, such as crystal engineering, topography engineering, heterostructures and support engineering, have been used to catalysts. Here we report RuO 2 supported on CeO 2 -NC, owing to the abundant heterostructures and the presence of oxygen vacancies, the RuO 2 /CeO 2 -NC catalyst showed outstanding HER performance (98.2 mV, 53 mV and 298 mV@100 mA cm−2 in acidic, alkaline and neutral, respectively). Moreover, RuO 2 /CeO 2 -NC also has an excellent electrocatalytic durability for 40 h. The experimental achievements show that oxygen vacancies and heterostructures could jointly enhance performance of catalyst HER. • CN-loaded CeO 2 composite RuO 2 structure. • We present a functionalization by arming RuO 2 nanoparticles with CeO 2 -NC enriched with oxygen vacancy, which can activate the superior HER catalytic activety. • The charge transport at the heterogeneous interface present in RuO 2 /CeO 2 -NC effectively enhances the reaction kinetics during electrocatalysis. • RuO 2 /CeO 2 -NC exhibits high activity and durability for hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

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

Photothermal synergistic catalysis (PTSC) is a potential and attractive technology due to its enhanced performance in medium- and low-temperature conditions. Herein, the present work focuses on investigating PTSC CO2 hydrogenation over Ni/ZrO2 doped with Ru. Compared with thermal catalysis, the NiRu0.23/ZrO2 resulted in higher CO2 conversion and CH4 selectivity at all temperature in PTSC condition. Among all the catalysts, NiRu0.02/ZrO2 exhibits the best performance, which the CO2 conversion reach 48.37% and the CH4 selectivity is close to 100% at 400 °C and PTSC. The NiRux bimetallic catalyst maintains excellent activity and stability after the catalyst durability test over 36 h. The characterization results reveal that appropriate Ru doping is beneficial for light absorption and enhances CO2 adsorption capacity and activation. The migration of electrons from Ru to Ni atoms proves that there is a strong electronic interaction between Ni and Ru metals in the catalysts. [ABSTRACT FROM AUTHOR]

Selective hydrogenation of carboxylic acids to alcohols is generally difficult due to the low reactivity of the carboxy group, and the development of effective catalysts enabling high yields of the target alcohols at low reaction temperatures (<473 K) is challenging. Herein, we found that SiO2‐supported FeOx‐modified Ru (Ru−FeOx/SiO2) with the Fe/Ru molar ratio of 0.4 was an effective and reusable heterogeneous catalyst for the hydrogenation of carboxylic acids at a low reaction temperature of 413 K, providing the alcohols in high yields (up to 97 %). The addition of Fe species drastically suppressed the hydrogenolysis of the C−C bond of the alkyl chain to methane, leading to high selectivity to the alcohols. Based on the activity tests and catalyst characterizations, Ru metals were covered by the reduced Fe species, such as Fe metal or Fe2+, and the active site is the interface between the Fe species and Ru metals. From the reactivity comparison of the related compounds, the alcohol is synthesized via the formation of the aldehyde, and the reactivity of the alcohol is very low in the presence of carboxylic acids. As a result, the hydrogenolysis of the produced alcohol is suppressed, leading to the high selectivity of the alcohol. [ABSTRACT FROM AUTHOR]

Multicomponent catalysts can be designed to synergistically combine reaction intermediates at interfacial active sites, but restructuring makes systematic control and understanding of such dynamics challenging. We here unveil how reducibility and mobility of indium oxide species in Ru‐based catalysts crucially control the direct, selective conversion of CO2 to ethanol. When uncontrolled, reduced indium oxide species occupy the Ru surface, leading to deactivation. With the addition of steam as a mild oxidant and using porous polymer layers to control In mobility, Ru−In2O3 interface sites are stabilized, and ethanol can be produced with superior overall selectivity (70 %, rest CO). Our work highlights how engineering of bifunctional active ensembles enables cooperativity and synergy at tailored interfaces, which unlocks unprecedented performance in heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Green Chemistry." It highlights various articles and research papers published in the journal, covering topics such as aqueous electrolyte additives, catalytic innovations in furfural transformation, renewable binders for battery systems, and the potential use of glycerol derivatives as bio-based building blocks. The journal aims to promote cutting-edge research for a greener and more sustainable future. [Extracted from the article]

Synthesis of novel benzothiazoles via intramolecular CS bond formation reactions is increasingly being explored since they have been found in a wide range of natural products and pharmaceutical agents. Sharma et al. reported the ruthenium‐catalyzed preparation of novel benzothiazole derivatives from N‐arylthiourea precursors, with a range of reaction yields and selectivity being observed. We have employed a density functional theory‐based computational model to investigate the reaction mechanism leading to the benzothiazole product and help uncover the origin of the differing experimental yields and substrate specificities. We proposed a modified mechanistic scheme where the rate‐determining step to be the synchronized breaking of the peroxide bond of the oxidizing agent with the concomitant proton‐coupled electron transfer from the haloarene urea and a Ru‐bound water molecule, not electrophilic RuC bond activation. Evidence for this being the rate‐determining step is (a) the barrier is consistent with a lack of kinetic isotope effects associated with the ortho‐H atom and (b) the computed rate‐determining barriers for 10 N‐arylthiourea substrates show good correlation with the observed yield. [ABSTRACT FROM AUTHOR]

The document is the contents list for the journal "Chemical Communications" published on October 4, 2024. It includes various articles and communications on topics such as solar energy, catalysis, coordination chemistry, and organic synthesis. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a comprehensive overview of the articles included in the issue, allowing library patrons to quickly identify relevant research topics. [Extracted from the article]

Exploring efficient and economical electrocatalysts to replace noble metal electrocatalysts has become a major research focus nowadays. In this paper, Ru-doped Co nanoparticles loaded on carbon nanosheet (CNS) in-situ grown on carbon nanofibers (Ru–Co@CNS/CNFs) were constructed as a self-supporting working electrode for high-efficiency hydrogen evolution. The prepared Ru–Co@CNS/CNFs possessed excellent catalytic activity with only 78 mV overpotential at 10 mA cm−2 current density and good stability with only 102 mV voltage attenuation at 100 mA cm−2 current density for 100 h continuous operation. The excellent catalytic performance could be attributed to the unique microstructure of the nanosheets in-situ grown on the nanofibers, it resulted in a higher Co surface density of 1.28 mg cm−2, indicating more loading of metal to improve catalytic activity of HER, and the formed Ru-doped Co nanoparticles could be evenly distributed on the carbon nanosheets to prevent the aggregation of nanoparticles, which could expose more active sites. Additionally, the density functional theory (DFT) calculations revealed Ru doping could accelerate the dissociation of water, optimize the adsorption energy of hydrogen intermediates and improve the kinetics of the HER reaction. This work provides a new approach to reduce the use of noble metals while improving the catalytic performance of catalysts. [Display omitted] • Microstructure of nanosheets in-situ grown on nanofiber was synthesized by electrospinning and immersion method. • The unique microstructure loaded more metal content and exposed more active site. • Ru doping accelerated water dissociation, optimized ΔG H* , and improved HER reaction kinetics. • The Ru–Co@CNS/CNFs catalyst possessed excellent catalytic performance (ƞ 10 = 78 mV, ƞ 100 = 228 mV). • It showed exceptional stability after testing for 100 h at the density of 100 mA cm−2. [ABSTRACT FROM AUTHOR]

Photothermal synergistic catalysis (PTSC) is a potential and attractive technology due to its enhanced performance in medium- and low-temperature conditions. Herein, the present work focuses on investigating PTSC CO2 hydrogenation over Ni/ZrO2 doped with Ru. Compared with thermal catalysis, the NiRu0.23/ZrO2 resulted in higher CO2 conversion and CH4 selectivity at all temperature in PTSC condition. Among all the catalysts, NiRu0.02/ZrO2 exhibits the best performance, which the CO2 conversion reach 48.37% and the CH4 selectivity is close to 100% at 400 °C and PTSC. The NiRux bimetallic catalyst maintains excellent activity and stability after the catalyst durability test over 36 h. The characterization results reveal that appropriate Ru doping is beneficial for light absorption and enhances CO2 adsorption capacity and activation. The migration of electrons from Ru to Ni atoms proves that there is a strong electronic interaction between Ni and Ru metals in the catalysts. [ABSTRACT FROM AUTHOR]

It has been known that plastics with undegradability and long half‐times have caused serious environmental and ecological issues. Considering the devastating effects, the development of efficient plastic upcycling technologies with low energy consumption is absolutely imperative. Catalytic hydrogenolysis of single‐use polyethylene over Ru‐based catalysts to produce high‐quality liquid fuel has been one of the current top priority strategies, but it is restricted by some tough challenges, such as the tendency towards methanation resulting from terminal C−C cleavage. Herein, we introduced Ru nanoparticles supported on hollow ZSM‐5 zeolite (Ru/H‐ZSM‐5) for hydrocracking of high‐density polyethylene (HDPE) under mild reaction conditions. The implication of experimental results is that the 1Ru/H‐ZSM‐5 (~1 wt % Ru) acted as an effective and reusable bifunctional catalyst providing higher conversion rate (82.53 %) and liquid fuel (C5−C21) yield (62.87 %). Detailed characterization demonstrated that the optimal performance in hydrocracking of PE could be attributed to the moderate acidity and appropriate positively charged Ru species resulting from the metal‐zeolite interaction. This work proposes a promising catalyst for plastic upcycling and reveals its structure‐performance relationship, which has guiding significance for catalyst design to improve the yield of high‐value liquid fuels. [ABSTRACT FROM AUTHOR]

Biomass valorisation through the selective oxidation of carbohydrate and lipid derivatives offers access to an array of platform chemicals through energy- and atom-efficient catalytic processes. Supported metal nanoparticles are promising catalysts for the aerobic selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), but typically require strong liquid base to achieve high selectivity. Here, we explore the utility of MgO as a solid base support for the Ru-catalysed aerobic oxidation of HMF, obtaining 68% FDCA yield at 160°C and 1.5 MPa of O2 using <1 mol-% metal. Biomass offers a sustainable alternative source of carbon to existing fossil resources that underpin the global chemical industry – on which we rely for fuels, plastics and pharmaceuticals. Combining ruthenium metal with Earth-abundant magnesium oxide creates an efficient catalyst for transforming sugar components of waste biomass into a valuable precursor for the sustainable manufacture of plastics. (Image credit: Priya Lokhande.) This article belongs to the 10th Anniversary Collection of RACI and AAS Award papers. [ABSTRACT FROM AUTHOR]

Active and robust electrocatalysts for acidic oxygen evolution reaction (OER) are of crucial importance for efficient proton exchange membrane water electrolyzer (PEM‐WE). Ruthenium (Ru) oxide has attracted considerable attention due to its high activity. However, the unsatisfying stability of Ru oxide in acidic OER environments hinders the application. Here, Ce‐doped RuO2 nanoparticles are designed and supported on Co─N─C material (Ce@RuO2/CoNC) for acidic OER. It is demonstrated that Ce@RuO2/CoNC delivers a super low overpotential of 150 mV and an excellent stability of 1000 h at 10 mA cm−2, outperforming most previously reported Ru‐based catalysts. The mass activity is estimated as 2365.5 AgRu−1 at 1.5 V (vs RHE), representing ≈2× advance compared to the best prior study. Furthermore, applied in a single‐cell PEM‐WE device, it can steadily operate for 1000 h at 200 mA cm−2. The studies show that Ce‐doping and Co─N─C support synergistically enhance the activity and stability of Ru oxide by optimizing the free energies of OER intermediates and suppressing the dissolution of Ru. [ABSTRACT FROM AUTHOR]

The activity profile of the new indenylidene complexes containing two unsymmetrical N‐heterocyclic carbene (NHC) ligands was investigated. They turned out to be effective in both straightforward olefin metathesis reactions, such as ring‐closing metathesis (RCM) of diethyl diallylmalonate, as well as in more demanding processes, such as RCM of 2,2‐di‐(2‐methylallyl)tosylate leading to a product bearing a tetrasubstituted double bond, and in selective ethenolysis of methyl and ethyl oleate. [ABSTRACT FROM AUTHOR]

The catalytic activity of a Ru complex 1, bearing a fused π‐conjugated imidazo[1,2–a][1,8]naphthyridine‐based mesoionic carbene (MIC) ligand, is examined for the oxidation of primary amines. Complex 1 affords nitrile or imine depending on the nature of the terminal oxidants and solvents used in the reactions. Primary amines are converted to nitriles using NaIO4 in EtOAc/H2O mixture, whereas imines are obtained under O2 balloon pressure in toluene. A variety of nitriles and imines are accessed with high yields and selectivity. A set of control experiments, reaction profiles, and kinetic studies are undertaken to disclose the mechanistic details for nitrile and imine formation. The catalytic reactions illustrate a subtle dependency on the choice of oxidants and solvents in the oxidation of primary amines. [ABSTRACT FROM AUTHOR]

ABSTRACT A new set of andrographolide‐appended hydrazide derivatives (AFC, AGC, and ATC) were prepared from the reaction of andrographolide with furan‐2‐carboxylic acid hydrazide (AFC), pyridine‐3‐carboxylic acid hydrazide (AGC), and thiophene 2‐carboxylic acid hydrazide (ATC), and their corresponding ruthenium(II) complexes (Ru‐AFC, Ru‐AGC, and Ru‐ATC) were synthesized by the direct reaction of [RuCl2(η6‐p‐cymene)]2 with ligands in dichloromethane under stirring condition. The compounds were analyzed by elemental analysis, IR, UV‐Vis, 1H NMR, and ESI‐MS spectrometric techniques, and the obtained spectral data revealed that the ligands coordinated to Ru(II) ion through their enone oxygen and amine nitrogen. Antioxidant activities of the ligands and complexes were calculated against DPPH•, ABTS•+, O2−, and NO• free radicals and their results were compared with standard antioxidants. The cytotoxic activity of the synthesized ligands and complexes toward A549 and HeLa cell lines was evaluated using MTT method (MTT = 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide). Among the compounds, the complex Ru‐AGC showed better cytotoxic effect against A549 and HeLa cancer cells with IC50 values of 4.75 ± 0.17 and 6.32 ± 0.26 μM, respectively. Further, the nontoxic nature of the compounds was confirmed by using human umbilical vein endothelial (HUVEC) cells. The apoptosis was inspected with AO/EB and DAPI staining methods; further, the percentages of the apoptotic and necrotic cells were determined by flow cytometry. Overall, the biological activities of our ruthenium(II)‐arene complexes were found to be more potent than their parent ligands due to chelation, and among the complexes, Ru‐AGC showed better activity due to the presence of pyridine ring in the N‐terminal position of the ligand. The obtained results highlighted the strong possibility to develop highly active ruthenium complexes as anticancer agents. [ABSTRACT FROM AUTHOR]

Efficcient elecctro-oxidation of 5-hydroxymethylfurfural (HMF) to produce 2,5-furandicarboxylic acid (FDCA) was achieved in a low-concentrated alkaline electrolyte over a single-atom-ruthenium supported on Co 3 O 4 (Ru 1 -Co 3 O 4). Single-atom-Ru enhances hydroxyl (OH–) adsorption, thereby improving the oxidation of HMF. The design for the Ru 1 -Co 3 O 4 catalyst enables efficient HMF-to-FDCA electrocatalysis without using strong alkaline electrolytes, which may greatly improve the profitability of HMF-to-FDCA electroccatalysis. [Display omitted] Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a sustainable strategy to produce bio-based plastic monomer, is always conducted in a high-concentration alkaline solution (1.0 mol L−1 KOH) for high activity. However, such high concentration of alkali poses challenges including HMF degradation and high operation costs associated with product separation. Herein, we report a single-atom-ruthenium supported on Co 3 O 4 (Ru 1 -Co 3 O 4) as a catalyst that works efficiently in a low-concentration alkaline electrolyte (0.1 mol L−1 KOH), exhibiting a low potential of 1.191 V versus a reversible hydrogen electrode to achieve 10 mA cm−2 in 0.1 mol L−1 KOH, which outperforms previous catalysts. Electrochemical studies demonstrate that single-atom-Ru significantly enhances hydroxyl (OH−) adsorption with insufficient OH− supply, thus improving HMF oxidation. To showcase the potential of Ru 1 -Co 3 O 4 catalyst, we demonstrate its high efficiency in a flow reactor under industrially relevant conditions. Eventually, techno-economic analysis shows that substitution of the conventional 1.0 mol L−1 KOH with 0.1 mol L−1 KOH electrolyte may significantly reduce the minimum selling price of FDCA by 21.0%. This work demonstrates an efficient catalyst design for electrooxidation of biomass working without using strong alkaline electrolyte that may contribute to more economic biomass electro-valorization. [ABSTRACT FROM AUTHOR]

The inclusion of ruthenium (Ru) to decorate nickel sulphide (Ru@NiS/Ni foam) resulted in a highly efficient electrocatalyst for the alkaline HER by enhancing water dissociation at the interface and reducing the energy barrier of the Volmer step. This strategic fusion significantly boosts the catalyst's performance in facilitating hydrogen production. [ABSTRACT FROM AUTHOR]

Chromophore–catalyst assemblies are interesting benchmark molecules for photocatalysis. We have prepared two examples of these assemblies and characterized their behaviour as catalysts for the water oxidation reaction. In the bimetallic complexes [Ru(tpy)(4,4′-X2-bpy)(μ-CN)Ru(bda)(DMSO)](PF6) (X = –H (1), –OCH3 (2), tpy = 2,2′:6′,2′′-terpyridine, bpy = 2,2′-bipyridine, H2bda = 2,2′-bipyridine-6,6′-dicarboxylic acid and DMSO = (CH3)2SO), a Ru(II)-polypiridine chromophore {Ru(tpy)(4,4′-X2-bpy)} is linked by a cyanide bridge to a {Ru(bda)} water oxidation catalyst. Both complexes catalyze water oxidation both chemically, using Ce(IV) as the terminal oxidant, and electrochemically. Electrochemical and spectroelectrochemical studies, aided with (TD)DFT calculations, allowed us to study the different species involved in the catalytic cycle. For the RuIIRuIII, an intense MMCT (metal-to-metal charge transfer) band suggests a geometrical reorganization during the oxidation process. The wave associated with oxidation to the RuIIIRuIV species shows an increased current that suggests that it may be a catalyst for the water oxidation reaction. Further oxidation results in the RuIIIRuV redox state which is an active catalyst for the water oxidation reaction as demonstrated by the evolution of oxygen. [ABSTRACT FROM AUTHOR]

Depletion of oil and gas resources is a major concern for researchers and the global community. Researchers are trying to develop a way to overcome these issues using the Fischer-Tropsch synthesis (FTS) process. The FTS reaction converts a mixture of hydrogen and carbon monoxide gases into a liquid fuel. The reactions are performed in the reactor and in the presence of a catalyst. A series of catalysts, such as iron, cobalt, nickel, and ruthenium, have been used for the FTS process. In iron-based catalysts, the Fe5C phase is the active phase that produces C5+ hydrocarbons. At higher conversion rates, the presence of water in the products is a problem for cobalt catalysts because it can trigger catalyst deactivation mechanisms. Ni-based catalysts play key roles as base catalysts, promoters, and photothermal catalysts in FTS reactions to produce different useful hydrocarbons. Ruthenium catalysts offer not only high activity but also selectivity toward long-chain hydrocarbons. Moreover, depending on the Ru particle size and interaction with the oxide support, the catalyst properties can be tuned to enhance the catalytic activity during FTS. The detailed reaction pathways based on catalyst properties are explained in this article. This review article describes the issues and challenges associated with catalysts used for the FTS process. [ABSTRACT FROM AUTHOR]

ABSTRACT The electrochemically driven asymmetric hydrogenation of 2,2,2‐trifluoroacetophenone was performed using a Noyori–Ikariya catalyst, yielding a 97% product yield and a 47% enantiomeric excess (ee) with a charge input of only 0.5 F/mol. In comparison, the ethoxylate anion generated by the electroreduction of the solvent, EtOH, can efficiently drive the transfer hydrogenation of Ru catalysts more effectively than organic bases. After optimizing the electrolysis conditions, this method has been successfully extended to other aromatic ketones, including heterocyclic aromatic ketones and the base‐sensitive substrate ethyl benzoylformate, with yields ranging from 71% to 97% and ee values ranging from 55% to 82%. A possible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Ionic liquids have been studied as CO2 capture agents. However, they are rarely used in combined CO2 capture and conversion processes. Utilizing imidazolium‐based ionic liquids, the conversion of CO2 to methanol was greatly improved in polyamine assisted systems catalyzed by homogeneous pincer catalysts with Ru and Mn metal centers. Among the ionic liquids tested, [BMIM]OAc was found to perform the best under the given reaction conditions. Among the polyamine tested, pentaethylenehexamine (PEHA) led to the highest conversion rates. Ru‐Macho and Ru‐Macho‐BH were the most active catalysts. Direct air capture utilizing PEHA as the capture material was also demonstrated and produced an 86 % conversion of the captured CO2 to methanol in the presence of [BMIM]OAc. [ABSTRACT FROM AUTHOR]

The hydrogenolysis of polymers is emerging as a promising approach to deconstruct plastic waste into valuable chemicals. Yet, the complexity of plastic waste, including multilayer packaging, is a significant barrier to handling realistic waste streams. Herein, we reveal fundamental insights into a new chemical route for transforming a previously unaddressed fraction of plastic waste – poly(ethylene‐co‐vinyl alcohol) (EVOH) and related polymer blends – into alkane products. We report that Ru/ZrO2 is active for the concurrent hydrogenolysis, hydrogenation, and hydrodeoxygenation of EVOH and its thermal degradation products into alkanes (C1−C35) and water. Detailed reaction data, product analysis, and catalyst characterization reveal that the in‐situ thermal degradation of EVOH forms aromatic intermediates that are detrimental to catalytic activity. Increased hydrogen pressure promotes hydrogenation of these aromatics, preventing catalyst deactivation and improving alkane product yields. Calculated apparent rates of C−C scission reveal that the hydrogenolysis of EVOH is slower than low‐density polyethylene. We apply these findings to achieve hydrogenolysis of EVOH/polyethylene blends and elucidate the sensitivity of hydrogenolysis catalysts to such blends. Overall, we demonstrate progress towards efficient catalytic processes for the hydroconversion of waste multilayer film plastic packaging into valuable products. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of carbon dioxide to formate is of great interest due to its significant role in CO2 utilization. In this study, a novel heterogeneous Ru(III) catalyst was prepared by immobilizing RuCl3 on a porous organic polymer (POP) obtained from 1,4-phthalaldehyde (PTA) and 4,4'-biphenyldicarboxaldehyde (BPDA) with melamine. A copolymerization strategy utilizing monomers of varying lengths was employed to prepare the POP-supported Ru catalyst with adjustable porosity. The optimization of the framework porosity resulted in enhanced CO2 affinity, accelerated mass transfer, and a remarkable enhancement in catalytic activity. A high turnover number (TON) of 2458 was achieved for the CO2 hydrogenation to formate in 2 h with catalyst Cat-3 under 3 MPa (CO2/H2 = 1: 1) at 120 °C in 1 M Et3N aqueous solution. Moreover, the Cat-3 demonstrated good recyclability and was able to be reused for five consecutive runs, resulting in a high total TON of 9971. [ABSTRACT FROM AUTHOR]

Investigating clean and sustainable hydrogen generation from water splitting requires cost‐effective and highly efficient electrocatalysts for the hydrogen evolution reaction (HER). Ruthenium (Ru)‐based heterostructure catalysts have emerged as promising alternatives to precious Pt, offering significant potential to overcome current bottlenecks. Recent advancements in Ru‐based heterostructure catalysts have focused on achieving a balance between catalytic activity and stability. An overview of these developments provides insights into catalytic mechanisms and facilitates the development of novel catalysts. This review begins with an exploration of the enhanced activity of heterostructure catalysts, followed by a critical summary of synthetic strategies employed to fabricate these catalysts and their catalytic performances for HER. Attention is then directed to experimental endeavors aimed at enhancing the HER performance of Ru‐based heterostructure catalysts. Finally, the opportunities and challenges in developing heterostructure catalysts from the perspectives of material design and synthesis are discussed. Through these discussions, a comprehensive understanding of Ru‐based heterostructure catalysts and inspiring future research directions is the aim to provide. [ABSTRACT FROM AUTHOR]

Exploring high-efficiency catalyst toward hydrogen evolution reaction (HER) for sustainable hydrogen production is critical for building a forthcoming hydrogen economy. Atomically dispersed catalysts have shown great promises for catalyzing HER yet further fine-tuning the coordination chemical environment to boost the performance is still challenging. Herein, we report the synthesis and electrocatalytic HER application of Ru single atoms dispersed in P, N co-doped porous carbon (Ru SAs@PNC). Spherical aberration corrected scanning transmission electron microscope (AC-STEM) analysis revealed the formation of atomically dispersed Ru single atoms. The as-prepared Ru SAs@PNC catalyst showed excellent HER activity in 1 M KOH, evidenced by a small overpotential of 21 mV @ 10 mA cm−2 and a low Tafel slope of 31 mV dec−1, both of which are comparable to the Pt/C benchmark catalyst. It also exhibited great durability for long-time operation, as demonstrated by negligible overpotential increase in the 50 h E -t test, and outperformed stability in the accelerated durability test. Such excellent HER performance is mainly attributed to the N, P co-doped chemical coordination environment that differs from most widely reported solely nitrogen-coordinated Ru single atoms. [Display omitted] • A facile approach to prepare N, P codoped atomically dispersed Ru catalyst is reported. • The catalyst exhibits intriguing HER catalytic performance in alkaline solution. • DFT calculations revealed the reason of the HER enhancement upon P introduction. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes highlights, feature articles, and communications on various topics related to chemistry. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The contents list provides a range of research articles on topics such as catalysts, perovskites, photoluminescence, and electrocatalysis. [Extracted from the article]

A mechanochemical‐enabled Ru‐catalyzed regioselective synthesis of 3,4‐isoxazoles and 3,4,5‐isoxazoles from terminal and internal alkynes and hydroxyimidoyl chlorides is reported. This solid‐state and solvent‐free approach carefully examines the impact of the milling conditions on regiocontrol in 1,3‐dipolar cycloadditions using mechanochemical means. The study reveals that milling frequency, jar material, and the choice of liquid additive for liquid‐assisted grinding (LAG) significantly influence the catalytic activity of the Ru catalyst. Transmission electron microscope (TEM) analysis confirms the crucial role of coordinating liquid additives such as acetone and cyclopentyl methyl ether (CPME) in stabilizing and reducing the size of the in‐situ formed Ru nanoparticles, which is essential for catalytic activity. The applicability of this protocol is further demonstrated through the synthesis of a library of 3,4‐ and 3,4,5‐isoxazoles from a wide range of terminal and internal alkynes with varying physical states and electronic properties that highlights the potential of this method for the synthesis of more complex target molecules. [ABSTRACT FROM AUTHOR]

A series of M/NiCo-Ferrite (M: Pt, Pd, Ru, and Rh) nanoparticles were successfully synthesized, through a facile sol–gel auto-combustion followed by impregnation-reduction approach, as a catalyst for hydrogen generation from hydrolysis of NaBH4. All synthesized samples were characterized by XRD, N2 adsorption–desorption method, ICP-OES, FE-SEM, and EDX analysis. Compared to the other samples, it was observed that the Rh/NiCo-Ferrite sample exhibited higher particle distribution and surface area. To evaluate the hydrogen generation rate, the hydrolysis was carried out at a temperature of 35 °C, with an aqueous solution containing 5 wt.% NaBH4 and 3 wt.% NaOH. The experimental findings indicate that the Rh/NiCo-Ferrite sample exhibited a superior rate of hydrogen generation, with an average value of 11,667 mL/min.gcat, compared to the other samples studied. Enhanced catalytic properties may be responsible for its high activity. In addition, the activation energy of hydrolysis of sodium borohydride over the Rh/NiCo-Ferrite sample was 54.5 kJ/mol which is lower than the activation energy of many Ferrite-based catalysts. Moreover, the re-usability test of the Rh/NiCo-Ferrite sample denoted a decline in the catalytic activity after 4 recycling experiments due to the alterations in morphology and the reduction in the quantity of active phase. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) loaded catalysts show high activity and selectivity for ammonia (NH3) synthesis via electrochemical reduction of nitrate (NO3−), but their practical application is still restricted by their high cost and insufficient stability. Herein, a multi‐component electrocatalyst of Ru nanoclusters loaded on phosphorus‐doped/phosphate‐modified and oxygen vacancy (OV)‐rich Fe/Fe3O4 composite nanorods (Ru@P‐Fe/Fe3O4) to synergistically promote electrocatalytic NO3− reduction reaction (NO3−RR)‐to‐NH3 performance via strong metal‐support interaction (SMSI) is reported. Impressively, the best Ru@P‐Fe/Fe3O4 catalyst exhibits outstanding NO3−RR activity, selectivity, and durability in 0.1 M KNO3 + 0.5 M KOH solution, with an NH3 yield rate of 14.37 ± 0.21 mgNH3 h−1 cm−2 (1710.71 ± 25 mgNH3 h−1 mgRu−1) at −0.75 V versus reversible hydrogen electrode (vs. RHE), an NH3 Faradaic efficiency (FE) of 97.2% at −0.55 V vs. RHE, and a superior stability over 50 h, suppressing most of reported Fe‐based and Ru‐based electrocatalysts. The characterizations and theoretical calculations unveil that the SMSI between Ru nanoclusters and P‐Fe/Fe3O4 composite nanorods can promote the generation of OV, tune the electronic structure of Ru species, and stabilize Ru nanoclusters, thereby reducing the reaction energy barrier of NO3−RR‐to‐NH3, inhibiting the competitive hydrogen evolution reaction, and boosting the NH3 yield rate NH3 FE, and stability. [ABSTRACT FROM AUTHOR]

Hydrogen production from the decomposition of ammonia is one of the promising methods to solve the problem of hydrogen storage and transportation. Currently, ruthenium‐based catalysts are widely recognized as highly active catalysts for ammonia decomposition reactions. Here, Ru nanoparticles (NPs) on yttrium oxide derived from yttrium carbonate precursor (c‐Y2O3) was successfully prepared by the impregnation method. A hydrogen production rate up to 31.5 mmol gcat−1 min−1 can be obtained over the 5% Ru/c‐Y2O3 catalyst at 450 °C with a weight hour space velocity (WHSV) of 30000 mL gcat−1 h−1, and the activity is stable during a test period of 120 h. The catalysts were characterized by a series of techniques such as TEM, CO‐chemisorption, XPS, and CO2‐TPD. Characterization results reveal that high metal dispersion of Ru NPs, strong metal support interaction, high concentration of oxygen vacancies, and suitable basicity of Ru/c‐Y2O3 catalyst all strongly influence on the catalytic performance in ammonia decomposition. NH3 temperature‐programmed surface reaction (NH3‐TPSR) results indicate that a strong NH3 adsorption activation and binding desorption of nitrogen ability on the surface of Ru/c‐Y2O3 catalysts are also beneficial for the high activity. These results provide a reference for the design of efficient Ru‐based ammonia decomposition catalysts for hydrogen production by tuning the precursor of Y2O3 support. [ABSTRACT FROM AUTHOR]

A series of a novel CAAC ligands featuring a spiro‐fluorene group have been synthesized and complexed with ruthenium alkylidenes, yielding the corresponding Hoveyda‐type derivatives as a new family of olefin metathesis catalysts. The novel complexes have been characterized by XRD, HRMS and NMR measurements. The synthetised complexes were tested in catalysis and showed good activity in olefin metathesis, as demonstrated on diethyl diallylmalonate and allyl acetate substrates. The unique backbone in the ligand with the large, yet inflexible condensed system renders interesting properties to the catalyst, exemplified by the good catalytic performance and improved Z‐selectivity. In addition, the complex can also serve as a hydrogenation catalyst in a consecutive (one‐pot) reaction. The latter reaction can convert allyl acetate to butane‐1,4‐diol, a valuable chemical intermediate for biodegradable polybutylene succinate (PBS). [ABSTRACT FROM AUTHOR]

Herein we demonstrate an effective and facile end‐capping technique for ring‐opening metathesis polymerization (ROMP) using readily available allyl compounds as a new type of terminating agents. This new type of end‐capping reactions, which are based on the base‐promoted decomposition of ruthenocyclobutane intermediates, introduce diene moiety onto the chain end of ROMP polymers while simultaneously deactivating the ruthenium complex. These termination reactions are highly efficient, typically completing within 1 minute at 0 °C with >95 % end‐capping fidelity. [ABSTRACT FROM AUTHOR]