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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]

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]

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]

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]

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]

Due to its abundant resources and advantages in transportation and storage, methane fueled solid oxide fuel cells (SOFCs) are highly needed. In this work, an exceptional internal reforming catalyst comprising in-situ exsolved NiRu bimetallic nanoparticles and oxygen-deficient layered double perovskite LaBaMn 1.6 Ni 0.3 Ru 0.1 O 5+δ (r-LBMNR) was prepared. Compared to the cell with LaBaMn 1.6 Ni 0.4 O 5+δ (r-LBMN) catalyst, the cell with a Ru-doping r-LBMNR catalyst layer, exhibits superior peak power output of 336 mW cm−2 and better durability with a less decay rate of 0.014% per hour in CH 4 fuel. The enhanced electrochemical performance can be attributed to the high oxygen ion and electron conductivities of the catalyst and the coupling of Ni and Ru sites with the oxygen-deficient r-LBMNR matrix This coupling activates CH 4 and H 2 O, promotes the oxidation of C atoms in CH 4 molecules, and enables reversible hydrogen spillover, ultimately leading to the production syngas of CO(g) and H 2 (g). [Display omitted] • Trace Ru-doping facilitating the exsolution of nanoparticles. • LaBaMn 1.6 Ni 0.3 Ru 0.1 O 5+δ was modified with abundant O v and exsolved NiRu alloy. • Cell can operate stably over 220 h with a degradation rate of 0.014% h−1. [ABSTRACT FROM AUTHOR]

A novel method for the production of a biofuel precursor and additive (γ-valerolactone) using in-situ generated hydrogen is reported. Firstly, a potential non-carbon fuel as hydrogen is generated from water through a photoelectrochemical approach employing a set of TiO 2 nanostructures synthesized by hydrodynamic anodization. Secondly, this system was coupled with a reactor in a way that the hydrogen produced reacts with levulinic acid in the presence of a ruthenium catalyst to yield γ-valerolactone. The preparation procedure of TiO 2 nanostructures was optimized and the influence of factors such as the rotation speed and the anodization media was investigated. The best photoelectrochemical performance corresponds to the nanostructure synthesized in lactic acid and using hydrodynamic conditions at a rotation speed of 1000 rpm. The optimal nanostructure was used as a photocatalyst for hydrogen production by water splitting, with the generated hydrogen being directly used for the transformation of levulinic acid into γ-valerolactone in the presence of a ruthenium catalyst supported on alumina. Using this optimal TiO 2 and the ruthenium catalyst, a yield to γ-valerolactone of 93 % was obtained in only 5 h at 60 °C and atmospheric pressure. [Display omitted] • Optimization of photoelectrochemical water splitting with titania nanostructures. • Tandem process: photoelectrocatalysis and conventional heterogeneous catalysis. • In-situ generated hydrogen for biofuel production. • Clean fuels: hydrogen and γ-valerolactone. [ABSTRACT FROM AUTHOR]

The efficient transformation of chemicals and electricity via electrocatalytic hydrogen evolution reaction (HER) plays a pivotal role in green hydrogen production. Both in academia and industry, the pursuit of designing and fabricating catalysts for HER that are not only efficient and robust but also environmentally friendly is of significant interest. In this work, a ruthenium catalyst doped with nickel was synthesized using a procedure-minimal and solvent-free method facilitated by microwave-assisted pyrolysis. The incorporation of alloying and optimized electronic structures has resulted in Ru-based nanocrystals that change the HER mechanism and enable enhanced activity. The optimal RuNi/C catalyst demonstrates an overpotential of only 15 mV at a current density of 10 mA cm−2, with a Tafel slope of 24 mV dec−1, surpassing the performance of the state-of-the-art Pt/C catalyst. Remarkably, the prepared catalyst exhibits admirable corrosion resistance, making it a highly promising candidate for green hydrogen production through seawater splitting. A ruthenium catalyst doped with nickel is synthesized through a solvent-free microwave treatment, and exhibits a Pt-surpassed activity towards HER. [Display omitted] • A ruthenium catalyst doped with nickel is synthesized via a green method. • The HER mechanism on ruthenium is transferred by the doped nickel. • The optimized catalyst shows a platinum-surpassed activity for HER. • Superior corrosion resistance and durability is achieved for seawater splitting. [ABSTRACT FROM AUTHOR]

A full-scale, 2-D, axially symmetric, heterogeneous, and transient mathematical model is utilized to evaluate the dynamic operation of a honeycomb monolithic reactor during CO 2 methanation. A base case is defined, which considers a step-type functionality for H 2 load reduction (−20%) and a Ni catalyst. The impacts of the catalyst type (Ni vs Ru), the functionality of the H 2 load disturbance, and the monolith's diameter on reactor performance are studied and compared to the base case. Results show that the use of Ru as catalyst, a ramp-type disturbance and a smaller reactor diameter generate a superior dynamic response to the H 2 feed disturbance as well as favorable effects on thermal behavior. This is despite the higher temperature gradient generated when using Ru. These findings suggest that the monolithic reactor is a viable technological option for CO 2 methanation under flow variations, such as those encountered when employing green hydrogen. [Display omitted] • Dynamic operation of a monolithic CO 2 methanation reactor is modeled. • Reactor behavior under a step-type H 2 -Load variation is evaluated. • A better dynamic performance is obtained with a Ru catalyst. • A good reactor response to step and ramp fluctuations of the H 2 load was evidenced. • A significant effect of the reactor diameter on the dynamic control was observed. [ABSTRACT FROM AUTHOR]

This work aims at investigating the potential of catalytic membrane reactors (CMRs) for ammonia production from renewable hydrogen. To achieve this objective, computer-aided process simulation is deployed using Aspen plus v14 simulation tool. A 1D model is developed to describe the integration of a ruthenium catalyst into a CMR equipped with inorganic membranes that are selective to NH 3 over N 2 and H 2. First, the CMR performance is studied across a broad spectrum of membrane properties and operating conditions. Subsequently, the CMR model is integrated into several Power-to-Ammonia (PtA) process layouts, which are optimized and techno-economically compared against a traditional PEM-based PtA production process, employing condensation for the purification stage. Key findings at the reactor level confirmed that beyond a selectivity threshold towards hydrogen of 10–20, both the degree of conversion and recovery tend to be generally independent of the membrane's selectivity. However, for producing pure ammonia permeate, highly selective membranes (>1000 towards H 2) depending on the pressure drop are found essential making this alternative elusive based on existing membranes. At the PtA level, results in terms of efficiency indicates that the use of membrane reactor increases the system efficiency by around ∼8% with respect to reference case while ∼15% enhancement is achieved with this process when using SOEC technology. When examining the final Levelized Cost of Ammonia (LCOA), incorporating a membrane reactor in conjunction with condensation separation results in a cost that nearly matches the reference case. Future research should focus on replacing the condensation process with a method of purification at lower pressures. This could potentially further improve efficiency and reduce the cost of the membrane reactor compared to the traditional one. • A reactor model for ammonia production using a ruthenium catalyst-based CMR was developed, analyzing a range of membrane properties and operating conditions. • MR shows over 90% higher ammonia conversion compared to conventional reactors. • The MR increased the system efficiency by around 8% with respect to reference cases. • MR process showed a marginal 2% increase in cost over the reference process. [ABSTRACT FROM AUTHOR]

Annealing as an experimental means is often used to treat various electrocatalysts for improving their hydrogen evolution reaction (HER) performance. Herein, in order to investigate the effect of hydrogen annealing temperature on the HER performance of RuO 2 -based electrocatalysts, commercial RuO 2 , self-synthesized RuO 2 , and self-synthesized RuO 2 /MoO 3 composite are annealed at 150, 300, 500, and 700 °C in a hydrogen atmosphere, respectively. It's found that RuO 2 is gradually deduced at 150 °C, ultimately, completely reduced to Ru under 300 °C. Meanwhile, the content of RuO 2 at the samples surface is gradually decreases as the annealing temperature increase to 700 °C. However, for all samples, the 500 °C annealed sample shows the best HER performance in acid solutions, including the lowest over potential, the smallest Tafel slope, and the largest double-layer capacitance. We inferred that the optimal HER performance of the 500 °C annealed samples maybe attributed to their appropriate Ru/RuO 2 ratio. Density functional theory (DFT) calculations reveal that significant electron transfer across the Ru/RuO 2 interface, thereby optimizing the adsorption free energy of H on Ru and RuO 2 , ultimately resulting in Ru/RuO 2 catalyst exhibiting better HER activity than bare Ru and RuO 2. The study provides guidance on the preparation of RuO 2 -based electrocatalysts for achieving efficient hydrogen evolution. [Display omitted] • Various commercial and self synthesized RuO 2 -based catalysts have been studied. • The annealing temperature of RuO 2 -based catalysts covers a wide range of 150–700 °C. • The adsorption free energies of H on different ratio of Ru/RuO 2 were calculated. • The effect mechanism of annealing temperature on HER activity of RuO 2 was analyzed. [ABSTRACT FROM AUTHOR]

Ba-based perovskite oxides rich in oxygen vacancies (OVs) are anticipated to possess robust electron-donating capabilities and other favourable properties, rendering them a promising support for Ru catalysts in NH 3 synthesis. Herein, a glucose-urea deep eutectic solvent calcinating method was developed to synthesize an OV-rich BaTiO 3 (BTO-H) support for Ru catalysts. The BTO-H-supported Ru (Ru/BTO-H) catalyst achieves an impressive NH 3 synthesis rate of 5133 μmol g cat –1 h−1 (256.7 mmol g R u –1 h−1) at 400 °C and 0.1 MPa, surpassing the performance of Ru catalysts supported on OV-poor BTO supports and other supported Ru catalysts. Physical characterizations and kinetic experiments reveal the multifaceted influence of OVs on enhancing the catalytic performance of Ru/BTO-H in NH 3 synthesis. OVs serve as electron donors to Ru catalyst, facilitating the activation and dissociation of N 2. Simultaneously, OVs act as hydrogen acceptors from the Ru surface, mitigating hydrogen poisoning effects. Additionally, OVs stimulate the formation of surface hydrides, not only providing active sites for N 2 activation but also bestowing an electron-donating effect on the supported Ru catalyst. The combined positive effects of OVs establish BTO-H as an outstanding support for Ru catalysts in NH 3 synthesis. • A glucose-urea DES calcinating method was used to synthesize BaTiO 3 (BTO) support. • BTO support had rich oxygen vacancies and large specific surface area (70 m2 g−1). • Oxygen vacancies in BTO support played multiple roles in NH 3 synthesis. • BTO-supported Ru catalyst exhibited an NH 3 synthesis rate of 5133 μmol g-1 cat h−1. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) has higher energy barrier and slower kinetics, which limits the efficiency of electrocatalytic water splitting. Developing efficient catalysts is of great significance for improving oxygen evolution performance. Therefore, we developed a low-dose ruthenium-doped copper-nickel bimetallic organic framework self-supported electrode (Ru x CuNi-MOF/CF). The prepared Ru 0·004 CuNi-MOF/CF has excellent electrocatalytic activity and stability. At the current density of 10 mA cm−2, the overpotential is only 203 mV in 1 M KOH electrolyte, and it can work continuously and stably for 100 h. The Tafel slope of Ru 0·004 CuNi-MOF/CF is 57.01 mV dec−1. The excellent electrocatalyst performance is attributed to the following three points: (1) The self-supporting material does not need adhesives to avoid the inhibition of the conductive ability of the catalyst. (2) The Cu2+/Ni2+ lattice site is replaced by Ruδ+, and the electron rearrangement improves the conductivity and catalytic activity of the material. (3) The presence of zero-valence ruthenium nanoparticles can further provide more active sites and improve the electrochemical reaction rate. This work provides new insights into fabricating ruthenium-doped bimetallic organic framework self-supported electrode for the study of oxygen evolution performance. • Ingenious use of substrate in situ conversion to provide part of the metal source, reduce the cost of the experiment. • The Ru 0·004 CuNi-MOF/CF exhibits excellent durability after 100 h of continuous operation. • The electronic structure is regulated by Ru0/Ruδ+ to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

This study prepared a series of cerium oxide-based catalysts with different metal ruthenium loadings using an initial wet impregnation method. The results demonstrate that the prepared 1.4Ru/CeO 2 catalyst exhibits outstanding catalytic performance and activity stability. Under the condition where the Ru loading is only 1.4 wt%, the catalyst achieves almost complete NH 3 conversion at 500 °C, with a hydrogen production rate of 16.59 mmol gcat−1 min−1. Furthermore, after a 48-h long-term test, the activity remains stable. Characterization tests show that the metal ruthenium is uniformly distributed on the surface of cerium dioxide, with particle sizes ranging from 3 to 6 nm. Notably, a structure characterized by lattice stripes overlapping between the metal and support is observed. Increasing the Ru loading can enhance the surface acidity sites of the catalyst and the interaction between the metal and the support, which plays a crucial role in the long-term stability of the catalyst. Additionally, the abundant oxygen vacancies in cerium dioxide and its low cerium oxidation-reduction potential facilitate electron transfer to ruthenium, enhancing the adsorption of NH 3 and accelerating the desorption of N 2. [Display omitted] • The catalytic performance is related to the dispersion of the metal and the oxygen vacancies on the surface of the support. [ABSTRACT FROM AUTHOR]

Oxides have traditionally been considered inert in hydrogen evolution reaction due to their strong adsorption of hydrogen. Here, we successfully prepared a novel RuCoWOx-400 catalyst by strategically adjusting the calcination temperature to manipulate the growth of oxide heterointerfaces. The characterization techniques reveal that RuCoWOx-400 is a porous structure and contains multiple heterogeneous interfaces to enhance catalytic activity. Additionally, the as-synthesized RuCoWOx-400 exhibits low overpotential of 93 mV at 10 mA cm−2 coupled with small Tafel slope of 37.22 mV dec−1 in 1 M KOH. Remarkably, the electrochemical performance of RuCoWOx-400 remains stable for up to 50 h. Moreover, the adsorption and desorption of water at Co, W, and Ru sites coordinate the hydrogen evolution reaction, highlighting the unique role of these elements in enhancing catalytic activity. This study underscores the potential of oxide materials in hydrogen evolution reaction, paving the way for further exploration and optimization in this field. [Display omitted] • Simple temperature-controlled calcination constructs heterogeneous RuCoWOx-400. • The synergistic effect of various metal oxides improves the performance of HER. • Heterogeneous interfaces optimize the electronic structure between metal oxides. • Porous and heterogeneous surface increased active area and active site. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of novel ruthenium(ii) complexes with nitron-type N-heterocyclic carbene ligands containing chelating (N -arylcarbamoyl)methyl or carboxymethyl groups have been synthesized. Their evaluation as precatalysts in the hydrogenation of ketones has revealed that the complex containing three N -mesityl groups (one on the carbamoyl- methyl moiety and two on the triazole moiety) is the most efficient one. [ABSTRACT FROM AUTHOR]

CO and H 2 S poisoning of Pt-based catalysts for hydrogen oxidation reaction (HOR) stands as one of the long-standing hindrances to the widespread commercialization of proton exchange membrane fuel cells. In this paper, a Ru/Ti 4 O 7 catalyst is successfully synthesized by the microwave-thermal method. This Ru/Ti 4 O 7 catalyst shows a much higher noble metal mass activity than those of commercial PtRu/C and conventional Ru/C catalysts. The performance of the Ru/Ti 4 O 7 catalyst under the exist of CO or H 2 S shows insignificant current decay, which is far superior to commercial PtRu/C and Pt/C catalysts. In this Ru/Ti 4 O 7 catalyst, the electron transfer between Ru and Ti to form d-p orbital hybridization is considered to be responsible for the favorable catalytic HOR performance and the corresponding CO and H 2 S tolerance. The interaction mechanism formed by electron transfer may open a promising way for the subsequent development of anti-poisoning catalysts for PEM fuel cell hydrogen oxidation reaction. [Display omitted] • Ru/Ti 4 O 7 catalyst shows a superior noble metal mass activity than those of commercial Pt–Ru/C based catalysts. • Ru/Ti 4 O 7 catalyst exhibits excellent resistance to CO poisoning. • The catalyst is extremely resistant to H 2 S while remaining CO-tolerant. • MSI of Ru/Ti 4 O 7 ensures catalytic activity and anti-poisoning properties. [ABSTRACT FROM AUTHOR]

The catalyst is crucial in enhancing productivity within the Fischer-Tropsch synthesis (FTS). The metal support interaction (MSI) plays a pivotal role in the FTS catalyst performance, impacting activity, stability, and selectivity. he configuration and composition of the catalyst dramatically impact MSI, with a strong MSI (SMSI) specified for the core-shell structure. In this study, two methods consisting of chemical treatment of etching and adding a promoter (Ru) for tuning the SMSI of the FTS catalyst are presented, and their footprints on the catalysts' performance are screened by utilizing various characterization tests, molecular dynamic simulation, and catalytic tests. It is recognized that the silica interfacial perimeter acts as a barrier that restricts the charge transfer and boosts the SMSI in the silica-coated catalyst. Conversely, the etched catalyst exhibits a moderate MSI, contributing to increased reducibility, stability, and activity. Furthermore, the Ru-doped etched catalyst represents the optimum MSI, resulting in the highest overall performance. [Display omitted] • The catalyst's structure, configuration, and composition significantly affect the metal support interaction (MSI). • Chemical etching and a promoter (Ru) are used to tune the SMSI of the FTS catalyst and intensify its performance. • The etched catalyst exhibits a moderate MSI, increasing ease of reduction, stability, and activity. • The etched catalyst undergoing doping with Ru with the outer shell of ceria promotes the formation of oxygen vacancies. • Ru NPs have a significant effect on the electron charge surface density of the catalyst. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) are considered the most efficient technology for the direct conversion of hydrocarbons to electrical energy. Although the commonly used Ni/YSZ cermet materials in SOFCs show excellent electrocatalytic properties in H 2 fuel, they suffer from carbon deposition problem when hydrocarbon fuels are used. In this work, we study the use of Ni 0 · 05 Ru 0.05 -Mo 2 C with a porous nanorod-shaped morphology as an internal reforming catalyst layer for methane-fueled SOFCs to solve the degradation of cell performance due to carbon deposition. The electrochemical performance and coking tolerance of two types of cells with and without the catalyst layer were systematically studied using methane and hydrogen as fuels. With the catalyst layer, the single cell using methane as fuel exhibits an improvement in peak power density by 24%, increasing from 297 to 367 mW cm−2 and there was no diffusion barrier for fuel gases within the cell. Furthermore, the cell can stably run for 100 h in methane at 700 °C. The improvement of electrochemical performance is attributed to the synergistic effect of Ni and Ru sites anchored on the porous Mo 2 C nanorods catalyst based on strong metal-support interactions, promoting the effective catalytic conversion of CH 4 to CO and H 2. This study demonstrates that the integration of a catalyst layer for internal reforming is an effective strategy for the direct use of methane in SOFCs. • Porous Mo 2 C nanorods loaded with Ni and Ru bimetal nanoparticles were prepared. • The NiRu–Mo 2 C nanorods were used as an internal reforming catalyst layer for SOFCs. • The NiRu–Mo 2 C nanorod catalyst layer improves the cell performance in CH 4. • The cell with the catalyst layer shows excellent long-term stability. [ABSTRACT FROM AUTHOR]

The development of electrocatalysts capable of efficiently catalyzing the alkaline hydrogen evolution reaction (HER) is crucial for driving the advancement of sustainable energy. Herein, by altering the surface state of the support, we transformed the bulk W 5 N 4 into a porous structure and constructed a Ru/W 5 N 4 heterostructure. The transfer of electrons from Ru to W 5 N 4 can optimize the electronic structure of the catalyst, thereby effectively promoting electron transfer, accelerating reaction kinetics, and enhancing the activity of the catalyst. Furthermore, W 5 N 4 can serve as a protective shell to stabilize Ru0, which is regarded as the active center in HER. The resulting Ru/W 5 N 4 exhibits excellent HER activity, requiring only overpotentials of 43 and 156 mV to achieve current densities of −10 and −100 mA cm−2, respectively. This work provides valuable insights into the rational construction of heterostructures to optimize HER performance. • The Ru/W 5 N 4 /NF catalysts were synthesized by a conventional two-step method. • Electronic interaction between W 5 N 4 and Ru can enhance the catalytic activity. • Interface engineering is an effective method to regulate the interfacial charge. • The W 5 N 4 greatly enhances the hydrogen evolution efficiency of Ru in alkaline medium. [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]

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]

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]

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 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]

Precision polishing using transition metal catalysts such as Pt and Ru, called catalyst-refereed etching, is employed to fabricate atomically smooth surfaces on optical devices, realizing the designed device performance. However, the catalyst surface is covered with post-processing products during processing, drastically decreasing the removal rate. To address this issue, this paper proposes using an Ru-based alloy catalyst. Density functional theory calculation results show that doping Ti to Ru significantly reduces the adsorption energy of post-processing products, suggesting that the active site of the catalyst is easily recovered. When polishing silica glass, the Ru 2 Ti catalyst significantly improves the removal rate stability and enables the fabrication of an atomically well-ordered smooth surface, similar to that polished using a Pt or Ru catalyst. • An Ru-based alloy catalyst is proposed for precision polishing of optics components. • Density functional theory calculations were performed to verify its effectiveness. • The considered Ru 2 Ti catalyst significantly improves the removal rate stability. • Doping Ti to Ru reduces the adsorption energy of the post-processing products. • The catalyst also enables the fabrication of atomically well-ordered smooth surfaces. [ABSTRACT FROM AUTHOR]

The effect of Al 2 O 3 , TiO 2 , ZrO 2 and Yttria-Stabilized Zirconia (YSZ) supports on the activity of the dry reforming of CH 4 towards syngas production was investigated for Rh and Ru catalysts. Ruthenium-based catalysts were found to generally be more active than Rh leading H 2 /CO ratios close to unity above 700 °C. Methane conversion turnover frequency (TOF) over Rh catalysts becomes optimum for Rh/YSZ followed by Rh/TiO 2 and Rh/ZrO 2 , and finally Rh/Al 2 O 3 , which exhibited the lowest activity. The performance order is different for Ru catalysts, with TOF being increased in the order Ru/Al 2 O 3

Novel catalysts for efficient formation of liquid organic hydrogen carriers (LOHCs) used in hydrogen storage and transport show great promise. Although Pt–Ru alloys have exhibited catalytic activities superior to those of Pt in the hydrogenation of toluene to methylcyclohexane, the origins are still unclear. Herein, we use density functional theory (DFT) to examine the mechanisms for toluene hydrogenation on Pt and various Pt–Ru bimetallic catalysts. The core@shell-type Ru@Pt(111) shows more thermodynamically and kinetically favored hydrogenation of toluene than pure Pt or Pt–Ru ordered structures. The origin of the improved catalytic activity on Ru@Pt(111) is examined by separating the strain and ligand effects between the core and shell layers. The ligand effect lowers the d-band center more pronouncedly; moreover, the favorable charge gain on the surface lowers the binding energies of reaction intermediates as well as the activation energies for each hydrogenation step. This work provides insight into the design of novel catalysts providing LOHCs for efficient hydrogen storage. [Display omitted] • Hydrogenation of toluene to methylcyclohexane on Pt and Pt–Ru catalysts was studied. • Ru@Pt(111) tunes the hydrogenation mechanism and favors the catalytic activity. • Ru@Pt(111) surface lowers the energy of the d-band center the most. • Ligand effect of Ru@Pt induces a favorable charge gain on the surface. [ABSTRACT FROM AUTHOR]

One potential strategy to develop hydrogen evolution electrocatalysts for producing sustainable hydrogen in water electrolysis is creating electrocatalysts with low-cost, high activity, and high stability. Herein, we show that low-loading metal-based tungsten oxide (WO 3) can be used as electrocatalysts for the hydrogen evolution reaction (HER) in acid, alkaline, and alkaline-seawater electrolytes. Among prepared electrocatalysts, rhodium (Rh)-WO 3 exhibits a high HER activity with the values of overpotential of 48, 116, and 98 mV to obtain a current density of 10 mA cm−2 in acid, alkaline, and alkaline-seawater electrolytes, respectively. In addition, the Rh-WO 3 electrocatalyst shows high stability during the HER operation for over 60,000 s. Besides, the application of Rh-WO 3 electrocatalyst as cathode and commercial ruthenium oxide (RuO 2) as an anode for overall water splitting show excellent efficiency with only a potential of 1.45 V to a current density of 10 mA cm−2 in the alkaline-seawater electrolyte. The Rh-WO 3 //RuO 2 cell also exhibits high stability for over 80,000 s and maintains a current of 15 mA cm2 at a cell voltage of 1.51 V. The results provide evidence that Rh-WO 3 can be a promising HER catalyst for sustainable hydrogen production via alkaline-seawater electrolysis application. [Display omitted] • Low loading of Rh was synthesized on WO 3 nanosheets. • 5 wt% Rh-WO 3 exhibits excellent HER activity in the alkaline-seawater electrolyte. • The hydrogen spillover effect can improve the HER activity for the catalysts. • 5 wt% Rh-WO 3 as cathode shows the excellent water splitting process in the alkaline-seawater electrolyte. [ABSTRACT FROM AUTHOR]

Oxygen reduction and evolution reactions (ORR/OER) have attracted tremendous attention as the means to provide sustainable energy solutions. Bifunctionality for ORR and OER is extremely crucial and relevant for regenerative fuel cell technology. Both reactions use precious metal-based electrocatalysts that are limited and expensive making a strong case to develop low-cost, active and stable electrocatalysts. We propose tailoring of Cobalt Porphyrin (Co–Pr) framework by introducing meso phenyl substituents in the Pr ligand and further substitution of phenyl group by ortho/para-anilino groups (CoTPP, CoTPP-o-NMe 3 , CoTPP-p-NMe 3) to design an efficient and selective bifunctional catalyst. Electrocatalysis by CoTPP-o-NMe 3 (ηORR/ηOER = 0.45/0.28 V) outperforms Ir/Ru and Pt based benchmark catalysts. Energy profile, scaling relationship, electrode potential, energy descriptor and FMO analysis performed in the DFT framework rationalize its excellent catalytic activity and selectivity for 4e− reduction of O 2 to H 2 O which is vital for hydrogen production and fuel cell applications. • Tailoring meso positions of Co-Pr to enhance its catalytic activity for ORR/OER. • CoTPP-o-NMe 3 , the best bifunctional catalyst with ηORR/ηOER of 0.45/0.28 eV. • Outperforms the benchmark Pt and Ir/Ru catalysts for ORR/OER. • Efficient even in presence of electrode potential. • Promotes 4e- selective reduction of O 2 to H 2 O. [Display omitted] [ABSTRACT FROM AUTHOR]

Molecular hydrogen (H 2) is one of the future energy carriers when replacing fossil sources. Enzymatic systems serve as an inspiration for the design of novel hydrogen evolving catalysts. Though several heterobimetallic Ru systems are known as catalysts for the hydrogen evolution reaction (HER), homogeneous mononuclear Ru systems have not been explored much. Here, a new mononuclear Ru(II) complex [ cis -RuCl 2 (PPh 3) 2 (κ 2- TL)] (TL = 2-thiophenyl benzimidazole) possessing distorted octahedral geometry, has been synthesised and characterized as an efficient catalyst for acid-assisted hydrogen evolution by using various spectroscopic techniques as well as quantum chemical calculations. When trifluoroacetic acid is used as the proton source, the complex shows remarkable catalytic activity towards H 2 production. Based on the DFT calculations, an EECC mechanism could be proposed for HER, consistent with the assignment of the observed redox transitions. • Interdisciplinary research on energy and environmental catalysis is required to develop renewable sources of energy. • Hydrogen has emerged as an alternative energy carrier due to its carbon-free burning. • Enzymatic systems serve as an inspiration for the design of novel hydrogen evolving catalysts. • Very few bio-inspired homogeneous mononuclear Ru mimics have been explored as HER electrocatalysts. • The reported work reveals design principles for future HER catalysts that can operate at ambient conditions. [ABSTRACT FROM AUTHOR]

On-site hydrogen production from the oxidative decomposition of NH 3 with a catalyst is highly required in the countryside where external heat is hardly supplied. In this study, Ru-based zeolite catalysts were prepared by impregnation and subsequent washing using RuCl 3 ·3H 2 O and HY zeolite or H-MOR zeolite for the oxidative decomposition of NH 3. The H-MOR-supported Ru catalyst could not be self-heated by feeding 80% NH 3 /20% O 2 to the catalyst bed at room temperature. By contrast, the HY-supported Ru catalyst underwent self-heating to approximately 773 K upon feeding the reactants owing to the heat released by NH 3 adsorption and oxidation, leading to excellent performance for the oxidative decomposition of NH 3 during five cycles of start-up tests. Characterization results indicated that the Cl-free Ru/HY catalyst exhibited self-heating due to the presence of small well-dispersed Ru metal particles and a large amount of surface acidic sites. [Display omitted] • HY or H-MOR zeolite was selected as a support for Ru-based zeolite catalysts. • Cl-free Ru/HY catalyst underwent self-heating to approximately 773 K upon feeding 80%NH 3 /20%O 2. • Cl species presented on the catalyst was needed for self-heating of Ru/H-MOR catalyst bed. • Cl-free Ru/HY catalyst exhibited stable catalytic activity during five start-up cycles. • This attributes to the presence of small well-dispersed Ru particles and a large amount of acid sites. [ABSTRACT FROM AUTHOR]

• Ce-doped TiO 2 supported RuO 2 catalyst with a low Ru loading was developed for the Deacon reaction. • The resultant catalyst exhibited an excellent catalytic activity even under oxygen-lean condition. • Elucidation on the effects of the doped Ce in the catalytic oxidation of HCl. Reducing the cost of RuO 2 /TiO 2 catalysts is still one of the urgent challenges in catalytic HCl oxidation. In the present work, a Ce-doped TiO 2 supported RuO 2 catalyst with a low Ru loading was developed, showing a high activity in the catalytic oxidation of HCl to Cl 2. The results on some extensive characterizations of both Ce-doped TiO 2 carriers and their supported RuO 2 catalysts show that the doping of Ce into TiO 2 can effectively change the lattice parameters of TiO 2 to improve the dispersion of the active RuO 2 species on the carrier, which facilitates the production of surface Ru species to expose more active sites for boosting the catalytic performance even under some harsh reaction conditions. This work provides some scientific basis and technical support for chlorine recycling. Ce-doped TiO 2 supported RuO 2 catalyst with a low Ru loading was developed for the catalytic oxidation of HCl to Cl 2 , exhibiting an excellent catalytic activity and a good stability. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel Ru/BPC catalysts were prepared by impregnating Ru metal into porous carbon derived from waste bio-tar as a carrier matrix activated by KOH. The results of the catalytic supercritical water gasification (SCWG) of glycerol showed a carbon gasification efficiency (CGE) of 64.1% and a H 2 yield of 20.9 mmol·g−1at 425 °C and 25 MPa for 20 min due to the synergistic effect of Ru and active alkali metals present in the Ru/BPC material. In the catalyst cycling experiments, the exposure of the active site in the catalyst further increased the catalytic activity, the H 2 yield increased from 21.0 mmol g−1 to 40.8 mmol g−1 with 82.1% CGE. Catalyst characterization indicates that the rich pore structure and the number of unsaturated carbon atoms of BPC enhanced the adsorption of Ru metal. This study provides new ideas for waste biomass resource utilization and cheap catalyst preparation for hydrothermal gasification process. [Display omitted] [ABSTRACT FROM AUTHOR]

CO selective methanation (CO-SMET) is as an ideal H 2 -rich gases purification measurement for proton exchange membrane fuel cell system. Herein, the graphene aerogel-mixed metal oxide (GA-MMO) supported Ru–Ni bimetallic catalysts are exploited for CO-SMET in H 2 -rich gases. The results reveal that a three-dimensional network structure GA-MMO aerogel with higher specific surface area, better thermal stability and more defects or structural disorders is formed when MMO:GO mass ratio is in the range of 1–4. After loading of Ru, more NiO are reduced to metallic Ni by hydrogen spillover effect, and thus obviously enhances the reactivity. The GA-MMO supported Ru–Ni catalyst exhibits more excellent metal dispersion, reducibility, stronger CO adsorption and activation than the MMO supported Ru–Ni catalyst, thereby resulting in better catalytic performance and stability. This work offers new insights into the construction of highly active catalyst for the efficient generation of high-quality H 2 from H 2 -rich gases. [Display omitted] • The GA-MMO aerogels are synthesized by layer-by-layer self-assembly method. • GA-MMO aerogel has better thermal stability and more surface defects. • Ru–Ni/GA-MMO shows superior metal dispersion and strong CO adsorption and activation. • 0.8 wt% Ru–Ni/GA-MMO is a potential catalyst for CO SMET. [ABSTRACT FROM AUTHOR]

The study of ruthenium catalysts for ammonia decomposition on carbonized and non-carbonized Al 2 O 3 nanofibers (ANF) showed that the activity of catalysts with carbonized supports (ANFC) was 2–3 times higher compared to non-carbonized ones. Thus, on Ru/ANFC and Ru/ANF the release of hydrogen reached 133.5 and 34.7 mmol H 2 /(min·g cat), respectively, whereas on Ru-BaAc/ANFC and Ru-BaAc/ANF, only 118.8 and 58.6 mmol H 2 /(min·g cat), respectively. On the average, the activation energy of ammonia decomposition on ANFC-supported catalysts is 15 kJ/mol lower than that value for ANF-supported catalysts. According to TEM data, Ru particles on ANFC are larger than on ANF, but are more evenly distributed. An increase in the activity of the catalyst correlates with a change in the electronic state of the active component. XPS data for Ru indicate a shift in the binding energy towards lower values when going from ANF to ANFC. [Display omitted] • 1D materials as supports for ammonia decomposition catalysts. • Ru supported on carbonized (ANFC) and non-carbonized (ANF) Al 2 O 3 fibers was studied. • Ruthenium particles on ANFC exceed in size those on ANF. • H 2 production over ruthenium ANFC-supported catalysts was 133.5 mmol H 2 /(min·g cat). • Activity of ANFC-supported catalysts 2-3 times exceeded that of ANF-supported ones. [ABSTRACT FROM AUTHOR]

We report a physical mixture of 1 wt% Ru/Al 2 O 3 with 10 wt% Ni/Al 2 O 3 obtained from the NiAl 2 O 4 phase as a highly active, durable, and cost-effective catalyst for the dry reforming of methane (DRM). Since the presence of Ru facilitates the reduction of Ni oxides, resulting in not only enhanced CH 4 conversion but also increased carbon deposits, the optimal formation of metallic Ni sites is a key factor for the mixed Ru-Ni catalyst. Here, we used a NiAl 2 O 4 /Al 2 O 3 catalyst and reduced it with CH 4 under reaction conditions for the limited formation of metallic Ni sites, depending on the reaction temperatures. As a result, this mixed catalyst showed higher performance for DRM than a Ru single catalyst with mild carbon deposits at both low (650 ℃) and high (800 ℃) temperatures taking advantage of improved cost-effectiveness, on top of that, the existence of a Ni catalyst compensated for the loss of activity of a Ru catalyst due to sintering. We also suggest different mechanisms for DRM over the Ru catalyst and Ni catalyst respectively from the results of temperature-programmed surface reaction and CH 4 /CO 2 cycling experiments. [Display omitted] • The presence of Ru facilitates the reduction of Ni oxides. • The optimal formation of metallic Ni sites is a key factor for the Ru-Ni catalyst. • A physical mixture of RuO 2 /Al 2 O 3 with NiAl 2 O 4 /Al 2 O 3 shows the best activity for DRM. [ABSTRACT FROM AUTHOR]

This work focuses on the utilization of a two stages inorganic membrane-based system to generate and recover decarbonized hydrogen in order to meet the targets set by the European Clean Hydrogen Partnership under the Strategic Research & Innovation Agenda 2021–2027. In the first stage, a CH 4 :CO 2 = 60:40 mixture simulating a biogas stream is used to generate a CO x -free hydrogen via steam reforming reaction carried out in a tubular Pd-Ag membrane reformer, packed with a novel non-commercial 7 wt%Ni-0.5 wt%Ru/La 0.3 Y 0.3 Zr 0.4 O x catalyst, prepared by solution combustion method. The catalyst was characterized by XRD, TPR and TEM techniques. The analyses reveal well-distributed active metal particles interacting differently with the support (weakly and strongly). In particular, the XRD pattern shows the formation of perovskite and nickel oxide in addition to the pyrochlore phase. This behaviour indicates a low solubility of Ni in the pyrochlore structure. Reaction measurements were carried out at a temperature of 673 K, in the total pressure range between 250 kPa ÷ 350 kPa, weight hourly space velocity (WHSV) of 0.2 h−1, H 2 O/CH 4 feed molar ratio between 1.5 and 2, feeding N 2 -sweep gas in the permeated side. As best results of Stage 1, CH 4 conversion equal to 99% (@ H 2 O/CH 4 feed molar ratio = 2 and feed pressure of 250 kPa) and a CO x -free H 2 recovery of 40% were reached. In the second stage, the unpermeated stream of Stage 1 rich in hydrogen was fed to a supported Pd/Al 2 O 3 membrane separator to further recover high grade hydrogen at the same temperature and total pressure set in Stage 1. The maximum hydrogen recovery equal to 67% was reached at 673 K and 350 kPa, with a purity of the recovered stream equal to 99.9%. The total hydrogen recovered in the permeate streams of Stage 1 and Stage 2 was equal to 80% of the total hydrogen produced during the steam reforming reaction, showing an average purity equal to 99.99%, which allowed to meet the established targets. The work further analized and discussed the experimental results of the integrated system by means of performance indexes. [ABSTRACT FROM AUTHOR]

It was found that the Na modification is beneficial to the synthesis of Ru single-atomic catalyst anchored on GO Na, which was prepared by one-step hydrothermal process. Importantly, the strong metal-support interaction facilitates the electron transfer from Ru SA to GO Na via d-π conjugation, thus lowering the electron density of Ru SA. Experimental results and DFT calculations confirmed that the low electron density of Ru SA can significantly weaken the absorption of H* intermediates and simultaneously accelerate the desorption of generated H 2 from catalyst surface. As a result, the Ru SA/GO Na displayed exceptional HER activity with an extremely low over-potential of 20 mV at 10 mA cm−2, outperforming the benchmark commercial Pt (21 mV over-potential) and Ru nanoparticles (212 mV over-potential) catalysts. When Eosin Y was employed as a light harvester, this Ru SA/GO Na achieves outstanding photocatalytic hydrogen production with a record-high apparent quantum efficiency of 65.2% at 520 nm. Moreover, single-atomic Pt, Pd, Au and Rh were also successfully anchored on the Na-functionalized GO support, suggesting the universality of Na-induced single-atomic synthesis. This work not only provides an effective method for the synthesis of single-atomic metal catalysts but also establishes the connection between the electronic structures of catalyst and performances. [ABSTRACT FROM AUTHOR]

Developing high-efficiency electrocatalysts viable for pH-universal hydrogen evolution reaction (HER) has attracted great interest because hydrogen is a promising renewable energy carrier for replacing fossil fuels. Herein, we present a facile strategy for fabricating ultra-fine Ru nanoparticles (NPs) decorated V 2 O 3 on the carbon cloth substrates as efficient and stable pH-universal catalysts for HER. Benefiting from the metallic property and electronic conductivity of V 2 O 3 matrix, the optimized hybrid (Ru/V 2 O 3 -CC) exhibits excellent HER activities in a wide pH range, achieving lower overpotentials of 184, 219, and 221 mV at 100 mA cm−2 in 0.5 M H 2 SO 4 , 1.0 M KOH and 1.0 M phosphate-buffered saline, respectively. Moreover, the electrode remains superior stability with negligible degradation after 5000 cyclic voltammetry scanning whether in acidic, alkaline or neutral media. Experimental results, combined with theoretical calculations, demonstrate that the interaction between Ru NPs and the support V 2 O 3 induces the local electronic density diversity, allowing optimization of the adsorption energy of Ru towards hydrogen intermediate H∗, thus favoring the HER process. The well-designed Ru/V 2 O 3 -CC electrocatalyst exhibits a high-efficient and pH-universal HER property, which is attributed to the ample active sites of ultrafine Ru NPs and good electronic transmission property of inert V 2 O 3. [Display omitted] • The fabricated Ru/V 2 O 3 -CC exhibits superior activity viable for pH-universal HER. • The electron transfer is optimized by introducing ultrafine Ru NPs on V 2 O 3. • V 2 O 3 modulates the electronic environment around Ru NPs and optimizes ΔG H∗ of Ru. [ABSTRACT FROM AUTHOR]

The upgrading of biogas to value-added syngas via reforming of biogas is of great significance from the perspective of green carbon science. A series of Ru based nano-catalysts (Ru/MgO, Ru/La 2 O 2 CO 3 , Ru/CeO 2) with relatively low Ru loading and high dispersion were successfully prepared by mechanochemical method, and applied in the bi-reforming of model biogas reaction. The representative catalysts were comprehensively characterized by XRD, N 2 physical adsorption, ICP-OES, SEM, XPS, H 2 -TPR, CO 2 -TPD, HRTEM, FTIR of CO adsorption, TPSR, TG, and Raman spectroscopy, etc. Ascribed to the appropriate basicity of MgO, homogeneous Ru dispersion with ultra-small particle size, and strong interaction between Ru ultra-small nano particles and MgO support, Ru/MgO exhibit higher CO 2 adsorption and activation, higher CH 4 activation and dissociation, compared with Ru/La 2 O 2 CO 3 , Ru/CeO 2 , which facilitate the formation of active oxygen species and intermediate coke removal, thus enhance the resistance to coke deposition and sintering. At reaction conditions of T = 750 °C and weight hourly space velocity = 32,400 mLg Cat −1 h−1, 0.5Ru/MgO catalyst exhibit satisfying catalytic activity (initial CH 4 /CO 2 conversation rate of 87/48%) and superior stability (stable for 150 h) with negligible deactivation rates. [Display omitted] • A serial of Ru-based catalysts supported on MgO, La 2 O 2 CO 3 and CeO 2 were prepared by mechanochemical method. • Ru/MgO show excellent catalytic performance in bi-reforming of model biogas. • The small Ru NPs, basic MgO, and interaction between Ru NPs and MgO result in satisfying catalytic performance. [ABSTRACT FROM AUTHOR]