Ru Clusters Research Articles

Unsaturated bi‐heterometal clusters in metal‐vacancy sites of 2D MoS2 for efficient hydrogen evolution

AbstractThe valence states and coordination structures of doped heterometal atoms in two‐dimensional (2D) nanomaterials lack predictable regulation strategies. Hence, a robust method is proposed to form unsaturated heteroatom clusters via the metal‐vacancy restraint mechanism, which can precisely regulate the bonding and valence state of heterometal atoms doped in 2D molybdenum disulfide. The unsaturated valence state of heterometal Pt and Ru cluster atoms form a spatial coordination structure with Pt–S and Ru–O–S as catalytically active sites. Among them, the strong binding energy of negatively charged suspended S and O sites for H+, as well as the weak adsorption of positively charged unsaturated heterometal atoms for H*, reduces the energy barrier of the hydrogen evolution reaction proved by theoretical calculation. Whereupon, the electrocatalytic hydrogen evolution performance is markedly improved by the ensemble effect of unsaturated heterometal atoms and highlighted with an overpotential of 84 mV and Tafel slope of 68.5 mV dec−1. In brief, this metal vacancy‐induced valence state regulation of heterometal can manipulate the coordination structure and catalytic activity of heterometal atoms doped in the 2D atomic lattice but not limited to 2D nanomaterials.

Enhanced production and control of liquid alkanes in the hydrogenolysis of polypropylene over shaped Ru/CeO2 catalysts

The hydrogenolysis of polypropylene waste to liquid hydrocarbons offers a promising pathway for the chemical recycling of waste polymers. This work describes the importance of reaction conditions and support morphology to produce high liquid yields with enhanced control of chain length over highly active shaped and non-shaped Ru/CeO2 catalysts. The shaped 2 wt% Ru/CeO2 exhibit high liquid alkane yields (58–81%) when compared to the non-shaped 2 wt% Ru/CeO2 (liquid yield: 34–58%) under optimized reaction conditions (220 °C, 16 h, 30 bar H2). In particular, the 2 wt% Ru/CeO2 nanocube catalyst exhibits the highest activity yielding lighter hydrocarbons. This was rationalized to be a combination of small Ru cluster formation and enhanced metal-support interactions. The influence of larger Ru particles (≥1.5 nm) was confirmed mechanistically using a computational density functional theory study on the hydrogenolysis of pentane (C5) to determine the favorable formation of methane in the non-shaped Ru/CeO2 catalyst.

Low Ruthenium Content Confined on Boron Carbon Nitride as an Efficient and Stable Electrocatalyst for Acidic Oxygen Evolution Reaction

AbstractTo date, only a few noble metal oxides exhibit the required efficiency and stability as oxygen evolution reaction (OER) catalysts under the acidic, high‐voltage conditions that exist during proton exchange membrane water electrolysis (PEMWE). The high cost and scarcity of these catalysts hinder the large‐scale application of PEMWE. Here, we report a novel OER electrocatalyst for OER comprised of uniformly dispersed Ru clusters confined on boron carbon nitride (BCN) support. Compared to RuO2, our BCN‐supported catalyst shows enhanced charge transfer. It displays a low overpotential of 164 mV at a current density of 10 mA cm−2, suggesting its excellent OER catalytic activity. This catalyst was able to operate continuously for over 12 h under acidic conditions, whereas RuO2 without any support fails in 1 h. Density functional theory (DFT) calculations confirm that the interaction between the N on BCN support and Ru clusters changes the adsorption capacity and reduces the OER energy barrier, which increases the electrocatalytic activity of Ru.

Low Ruthenium Content Confined on Boron Carbon Nitride as an Efficient and Stable Electrocatalyst for Acidic Oxygen Evolution Reaction.

To date, only a few noble metal oxides exhibit the required efficiency and stability as oxygen evolution reaction (OER) catalysts under the acidic, high-voltage conditions that exist during proton exchange membrane water electrolysis (PEMWE). The high cost and scarcity of these catalysts hinder the large-scale application of PEMWE. Here, we report a novel OER electrocatalyst for OER comprised of uniformly dispersed Ru clusters confined on boron carbon nitride (BCN) support. Compared to RuO2 , our BCN-supported catalyst shows enhanced charge transfer. It displays a low overpotential of 164 mV at a current density of 10 mA cm-2 , suggesting its excellent OER catalytic activity. This catalyst was able to operate continuously for over 12 h under acidic conditions, whereas RuO2 without any support fails in 1 h. Density functional theory (DFT) calculations confirm that the interaction between the N on BCN support and Ru clusters changes the adsorption capacity and reduces the OER energy barrier, which increases the electrocatalytic activity of Ru.

Dense Ru single-atoms integrated with sulfoacids for cellulose valorization to isosorbide

Metal-acid bifunctional catalysts are the unity of two opposites (metal-acid repelling) for cellulosic biomass valorization to isosorbide. It is challenging to improve the selectivity of metal hydrogenation catalysts and their synergism with acids for catalytic hydrolysis and dehydration to achieve substantial isosorbide. Herein, dense Ru single-atoms (10.1 wt% of Ru SAs) are anchored on sulfoacid-functionalized hollow mesoporous carbon shells, designed by assembling silica and 8-hydroxyquinoline-modified chitosan (HQ-CTS) through in situ Stöber templating strategy before pyrolysis and acid treatment. Based on X-ray absorption fine structure and computational modeling results, the structure of Ru SAs is determined as RuN4, which is more selective for a transitional glucose hydrogenation to sorbitol than Ru001 of Ru clusters. A lower-energy barrier of 1.21 (0.72) eV is delivered over RuN4 (Ru001) for glucose hydrogenation (isomerization). These Ru SAs are integrated with sulfoacids (SO3H) but resistent against acids, rendering enhanced isosorbide yield in water as compared to Ru clusters, via a one-pot cascade reaction under harsh conditions (220 °C, 6 MPa H2). The elaborately fabricated dense Ru SAs and sulfoacids, achieved by varying the addition time of HQ-CTS during the in situ Stöber templating process, improve the synergism of glucose hydrogenation with cellulose hydrolysis and sorbitol dehydration. This study provides a new idea for rational design of high-performance metal-acid bifunctional catalysts toward one-pot conversion of cellulose to isosorbide.

Light-assistance in nitrogen fixation to ammonia by highly dispersed Cs-promoted Ru clusters supported on ZrO2

Light-assisted N2 fixation to NH3 under mild conditions is attracting massive attention to circumvent energy crisis and global warming. Herein, highly dispersed Cs-decorated Ru sub-nanometric clusters supported on ZrO2 NPs have been prepared by means of MOF-templated transformation method. The obtained catalyst exhibited N2 hydrogenation activity of 1.6 mmolNH3 gcat−1 h−1 in the dark (350 °C, 0.1 MPa). Remarkably this value increased by over 300 %, reaching 5.1 mmolNH3 gcat−1 h−1 (204 mmolNH3 gRu−1 h−1) under 1 Sun power illumination (1080 W/m2) The influence of the incident light wavelength has been evaluated, revealing 81 % and 213 % enhancement in the NIR and visible region, respectively. DFT calculations were carried out to understand the static adsorption states of Ru sub-nanoclusters. Mechanistic studies have confirmed the co-existence of a photothermal and a nonthermal-hot electron mechanism. XPS, PXRD and FTIR analysis have determined that the Cs species block surface Zr4+ acidity, increasing the basicity of the ZrO2 support. Moreover, partially reduced Csδ+ (0 <δ < 1) species surrounding the Ru active sites are donating electron density to the adjacent Ru sites, favoring N2 adsorption and subsequent activation. Finally, this photocatalyst has shown an extended stability for 100 h irradiation under continuous flow.

Constructing built-in electric field via ruthenium/cerium dioxide Mott-Schottky heterojunction for highly efficient electrocatalytic hydrogen production

Ensuring the consumption rate of noble metals while guaranteeing satisfactory hydrogen evolution reaction (HER) performance at different pH values is imperative to the development of Ru-based catalysts. Herein, we design a Mott-Schottky electrocatalyst (Ru/CeO2) with a built-in electric field (BEF) based on density functional theory (DFT). The Ru/CeO2 achieves the criterion current density of 10 mA cm−2 at overpotentials of 55 mV, 80 mV, and 120 mV in alkaline, acidic and neutral media, respectively. Both theoretical calculations and experimental analysis confirm that the improved HER activity in the Ru/CeO2 catalyst could be due to the successful construction of BEF at the interface between the prepared Ru clusters and CeO2. Under the action of BEF, the electron-deficient Ru atoms can optimize the adsorption energy of H* and H2O and thus promote HER kinetics. Furthermore, the Ru/CeO2 catalyst delivers a power density of approximately 94.5 mW cm−2 in alkaline-acidic Zn-H2O cell applications while maintaining good H2 production stability. In this work, we optimize the electrocatalytic performance of the Ru/CeO2 catalyst through examination of the interfacial BEF electrical charge, which combines hydrogen production with power generation and provides a promising method for sustainable energy conversion.

High-temperature mechanical performance of Ru doped cermets

The mechanical properties degradation of cermets under high temperatures greatly limits their applications. In this paper, the compressive yield strength of WC-Co based cermets at high temperatures was significantly improved by the addition of Ru. Based on the detailed microstructure analyses, the contribution of Ru to the plastic deformation of the cermets was disclosed. The addition of Ru would stabilize the fcc-Co structure, leading to an increase in the proportion of the coherent WC/Co phase boundaries. The coherent phase boundaries are beneficial to avoid stress concentration across the interface and premature crack initiation, inducing higher dislocation densities and larger plastic deformation in both Co and WC phases. The solid solution strengthening effect of Ru and the Ru cluster in the Co phase can inhibit the softening of the binder phase at high temperatures. The synergy of solid solution strengthening and dislocation strengthening is responsible for the higher yield strength of WC-Co cermets with Ru at high temperatures.

Supported Ruthenium Single-Atom and Clustered Catalysts Outperform Benchmark Pt for Alkaline Hydrogen Evolution.

Guaranteeing satisfactory catalytic behavior while ensuring high metal utilization has become the problem that needs to be addressed when designing noble metal based catalysts for electrochemical reactions. Here, the well-dispersed ruthenium (Ru) based clusters with adjacent Ru single atoms (SAs) on layered sodium cobalt oxide (Ru/NC) is demonstrated to be a superb electrocatalyst for alkaline HER. The Ru/NC catalyst manifests an activity increase by a factor of two relative to the commercial Pt/C. Operando characterizations in conjunction with density functional theory (DFT) simulations uncover the origin of the superior activity and establish a structure-performance relationship, that is, under HER condition, the real active species are Ru SAs and metallic Ru clusters supported on the NC substrate. The excellent alkaline HER activity of the Ru/NC catalyst can be understood by a spatially decoupled water dissociation and hydrogen desorption mechanism, where the NC substrate accelerates the water dissociation rate, and the generated H intermediates would then migrate to the Ru SAs or clusters and recombine to have H2 evolution. More importantly, comparing the two forms of Ru sites, it is the Ru cluster that dominates the HER activity. This article is protected by copyright. All rights reserved.

Theory-guided design of electron-deficient ruthenium cluster for ampere-level current density electrochemical hydrogen evolution

Ru-based materials have regarded as ideal alternatives to Pt-based catalysts for hydrogen evolution reaction (HER), however, strong adsorption of H intermediate for Ru-based catalysts results in an unsatisfactory HER activity. Herein, we perform a high-throughput computational screening of different Ru clusters that supported on a carbon substrate embedded with various non-precious metals by comparing their structure stability and adsorption energy of H intermediate. Guided by the computational predictions, a unique 3D catalyst of Ru cluster with a size of < 2 nm anchored on spherical carbon shell confining Ni particles (Ru/Ni@C) is developed. Owing to the strong metal-substrate interaction and optimized electronic structure, Ru/Ni@C exhibits an outstanding HER performance with an ultra-low overpotential of 309 mV at 1.0 A cm−2, outperformed commercial Pt/C and Ru/C catalysts. Experimental observations and theoretical calculations demonstrate the efficient electron transfer from anchored Ru cluster to core Ni particles via carbon layer, which leads to the formation of electron-deficient Ru site, beneficial to adjust the ability of H adsorption and eventually promotes the whole HER process.

Rational Design of Heterostructured Ru Cluster‐Based Catalyst for pH Universal Hydrogen Evolution Reaction and High‐Performance Zn‐H2O Battery

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

Process-intensified protonic ceramic fuel cells for power generation, chemical production, and greenhouse gas mitigation

•Simultaneous power generation, chemical production, and greenhouse gas mitigation •Sm0.2Ce0.7Ni0.1Ru0.05O2-δ catalyst was designed for dry reforming of methane •Extensive studies were performed to probe the synergistic impacts of Ni and Ru •At 650°C, the DRM-PCFC attained a peak power density of 0.94 W cm−2 Here, we present protonic ceramic fuel cells (PCFCs) that achieve the internal dry reforming of methane (DRM) at 550°C–650°C to simultaneously generate power, produce syngas or hydrogen as chemical building blocks, and to mitigate two harmful greenhouse gases. We developed an oxide-supported in situ exsolved Ni-Ru catalyst (Sm0.2Ce0.7Ni0.1Ru0.05O2-δ, i.e., SDC-Ni-Ru). The in situ exsolved Ru clusters favor the CO2 activation step, while the Ni clusters promote the CH4 activation. The synergy between Ni and Ru clusters simultaneously improves the CH4 and CO2 activation, enhancing the DRM activity. Additionally, we discovered that the Ru clusters alter the DRM pathway, favoring the formation of monodentate carbonate species, which subsequently accelerates the oxidization of −CH∗ species on Ni clusters and improves the coking tolerance. The PCFCs equipped with this SDC-Ni-Ru internal DRM catalyst attain exceptional and durable power densities using a mixture of CH4 and CO2 as the fuel, setting a record for DRM-PCFCs. Here, we present protonic ceramic fuel cells (PCFCs) that achieve the internal dry reforming of methane (DRM) at 550°C–650°C to simultaneously generate power, produce syngas or hydrogen as chemical building blocks, and to mitigate two harmful greenhouse gases. We developed an oxide-supported in situ exsolved Ni-Ru catalyst (Sm0.2Ce0.7Ni0.1Ru0.05O2-δ, i.e., SDC-Ni-Ru). The in situ exsolved Ru clusters favor the CO2 activation step, while the Ni clusters promote the CH4 activation. The synergy between Ni and Ru clusters simultaneously improves the CH4 and CO2 activation, enhancing the DRM activity. Additionally, we discovered that the Ru clusters alter the DRM pathway, favoring the formation of monodentate carbonate species, which subsequently accelerates the oxidization of −CH∗ species on Ni clusters and improves the coking tolerance. The PCFCs equipped with this SDC-Ni-Ru internal DRM catalyst attain exceptional and durable power densities using a mixture of CH4 and CO2 as the fuel, setting a record for DRM-PCFCs.

Spiral Square Nanosheets Assembled from Ru Clusters.

Spiral two-dimensional (2D) nanosheets exhibit unique physical and chemical phenomena due to their twisted structures. While self-assembly of clusters is an ideal strategy to form hierarchical 2D structures, it is challenging to form spiral nanosheets. Herein, we first report a screw dislocation involved assembled method to obtain 2D spiral cluster assembled nanosheets (CANs) with uniform square morphology. The 2D spiral Ru CANs with a length of approximately 4 μm and thickness of 20.7 ± 3.0 nm per layer were prepared via the assembly of 1-2 nm Ru clusters in the presence of molten block copolymer Pluronic F127. Cryo-electron microscopy (cryo-EM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) demonstrate the existence of screw dislocation in the spiral assembled structure. The X-ray absorption fine structure spectrum indicates that Ru clusters are Ru3+ species, and Ru atoms are mainly coordinated with Cl with a coordination number of 6.5. Fourier-transform infrared (FT-IR) spectra and solid-state nuclear magnetic resonance hydrogen spectra (1H NMR) indicate that the assembly process of Ru clusters is formed by noncovalent interactions, including hydrogen bonding and hydrophilic interactions. Additionally, the Ru-F127 CANs exhibit excellent photothermal conversion performance in the near-infrared (NIR) region.

Cation Vacancy Clusters in Ti3C2Tx MXene Induce Ultra‐Strong Interaction with Noble Metal Clusters for Efficient Electrocatalytic Hydrogen Evolution

AbstractMXenes are promising substrates for supported noble metal electrocatalysts. Yet, it is a significant challenge to modulate the metal–support interaction (MSI) for enhancing catalytic performance. Herein, employing a facile HF etching method, the cation vacancy structures in Ti3C2Tx MXenes are controllably tuned, producing nearly vacancy‐free (Ti3C2Tx‐V0), single Ti atom vacancy (Ti3C2Tx‐VS), or Ti vacancy cluster (Ti3C2Tx‐VC) engineered MXenes. Ruthenium atomic clusters, as a model catalyst, successfully anchor on all MXene substrates. Different from the terminal O/F coordination groups on routine Ti3C2Tx MXene surfaces, the Ti vacancy clusters in Ti3C2Tx‐VC create unique lattice carbon ligand environment toward Ru species, which induces ultra‐strong MSI. As a result, compared to Ti3C2Tx‐V0 and Ti3C2Tx‐VS, the Ti3C2Tx‐VC modulated Ru clusters (Ru@Ti3C2Tx‐VC) exhibit the optimized balance of H2O adsorption/dissociation and OH/H desorption, thereby delivering superior electrocatalytic performance in the alkaline hydrogen evolution reaction (HER). Within the wide range from laboratory‐level (90 mA cm−2) to industrial‐level (1.5 A cm−2) current density, Ru@Ti3C2Tx‐VC outperforms commercial Pt/C in terms of overpotential and mass activity. Moreover, as a universal substrate for noble metal catalysts, Ti3C2Tx‐VC can also anchor Ir/Pt/Rh atomic clusters and enable excellent HER catalytic activity. This work expands the scope of the MSI between MXene and noble metal catalysts.

Size effect of ruthenium nanoparticles on water cracking properties with different crystal planes for boosting electrocatalytic hydrogen evolution

Small size ruthenium (Ru) nanoparticles have shown remarkable potential for electrocatalytic hydrogen evolution reaction (HER). Nevertheless, the complicated preparation and relatively low activity of small size Ru nanoparticles are two key challenges. In this work, carbon nanotubes supported Ru nanoparticles catalysts (cnts@NC-Ru t °C) with different sizes were prepared via using the combination of L-3,4-dihydroxyphenylalanine (l-dopa) self-polymerization oxidation reaction and different high temperature annealing to study the variation of particle activity with size. Electrochemical test results showed that the optimized cnts@NC-Ru 700 °C catalyst exhibited a very low overpotential at 10 mA/cm2 (21 mV) and tafel slope of 34.93 mV/dec when the mass loading of precious metal per unit area was merely 12.11 μg/cm2 that surpassed most recently reported high-performance Ru based catalyst. The results of density functional theory (DFT) calculation showed that small Ru nanoparticles had abundant active sites, and the H2O dissociation on small Ru nanoparticles (110) surface is quite easy than other surfaces, while (111) surface of small Ru nanoparticles is beneficial for Tafel step of HER. The synergy between (110) and (111) surfaces on the Ru cluster contributes to its outstanding HER performance. This study provides a novel design idea in promoting the preparation method and uncovering the reason of high activity of small size Ru nanoparticles.

Electrochemical Oxidation Encapsulated Ru Clusters Enable Robust Durability for Efficient Oxygen Evolution.

Electrochemical oxidization and thermodynamic instability agglomeration are a primary challenge in triggering metal-support interactions (MSIs) by immobilizing metal atoms on a carrier to achieve efficient oxygen evolution reactions (OER). Herein, Ru clusters anchored to the VS2 surface and the VS2 nanosheets embedded vertically in carbon cloth (Ru-VS2 @CC) are deliberately designed to realize high reactivity and exceptional durability. In situ Raman spectroscopy reveals that the Ru clusters are preferentially electro-oxidized to form RuO2 chainmail, both affording sufficient catalytic sites and protecting the internal Ru core with VS2 substrates for consistent MSIs. Theoretical calculations elucidate that electrons across the Ru/VS2 interface aggregate toward the electro-oxidized Ru clusters, while the electronic coupling of Ru 3p and O 2p orbitals boosts a positive shift in the Fermi energy level of Ru, optimizing the adsorption capacity of the intermediates and diminishing the migration barriers of the rate-determining steps. Therefore, the Ru-VS2 @CC catalyst demonstrated ultra-low overpotentials of 245mV at 50mAcm-2 , while the zinc-air battery maintained a narrow gap (0.62V) after 470h of reversible operation. This work has transformed the corrupt into the miraculous and paved a new way for the development of efficient electrocatalysts.

Atomic ruthenium modification of nickel-cobalt alloy for enhanced alkaline hydrogen evolution

Density functional theory (DFT) is used to predict the behavior of ruthenium-doped nickel cobalt alloy in the alkaline hydrogen evolution reaction (HER). According to DFT calculation, a synergistic effect at the Ru-Ni/Co interface is generated to accelerate water dissociation and optimize the adsorption-desorption energetics toward the H intermediate. However, excessive Ru introduction will lead to over-strong hydrogen adsorption on the catalyst surface, thus limiting H2 release. As a proof of concept, we design a series of NiCoRux/SP, among which the optimized NiCoRu0.2/SP electrocatalyst achieves an overpotential of 59 mV at 10 mA cm−2, while excessive Ru incorporation (NiCoRu0.3/SP) diminishes the HER activity. X-ray absorption spectroscopy and other characterizations further confirm that the interface-induced electron transfer from atomic Ru to its surrounding Ni/Co, and the activity degradation caused by excessive Ru incorporation is attributed to the generation of Ru cluster that sacrifices the interface between Ru atom and Ni/Co.

Synergistic effect between Ru cluster and Co3O4 nanowires assisted by B-O bonding for hydrogen evolution

Anchoring noble metal nanoclusters (NCs) on appropriate supports through structural engineering is an effective strategy for reducing the noble metal loading and improving catalytic activity for alkali hydrogen evolution reaction (HER). Generally, the local coordination environment of the active sites is key factor to regulate the interaction between the metal atoms and support. Here, a simple boronation method is proposed for preparing ruthenium nanoclusters anchored on B-doped Co3O4 nanowires supported on Ni foam (denoted as Ru/B-Co3O4) for alkaline HER. B embedded into Co3O4 nanoarrays through B-O bonding can change the electronic structure between Ru active sites and Co3O4. After optimizing electronic structure of Ru and Co sites, Ru/B-Co3O4 showed remarkable activity for HER, with current density of 100 and 500 mA cm−2 at overpotential of 143 and 233 mV, respectively. The experimental and theoretical studies display that the embedding of B into Co3O4 effectively induces the electron transfer from Co to Ru atoms by bridging O atom, leading to the formation of electron-deficient Co sites. The charge redistribution of Ru accelerates the cleavage of H-OH, which optimizes H* adsorption energy and finally promotes HER. This study provides further insight into the regulation of metal-support interaction for HER electrocatalysts.

Highly active and durable chlorobenzene oxidation catalyst via porous atomic layer coating of Ru on Pt/Al2O3

Herein, we designed and fabricated a novel subnanometer Ru-coating Pt/Al2O3 catalyst (named RuPt-ALD) via atomic layer deposition (ALD), which showed an excellent capability of tuning catalysts’ structure-property relationship for chlorobenzene (CB) oxidation. Subnanometer Ru clusters were separately decorated onto Pt nanoparticles, while leaving neighboring Pt surfaces exposed, which could effectively enhance the substrate-particles interaction by electron donation. RuPt-ALD provided optimal activity and selectivity, and a stable CB conversion of ∼98 % for 600 min at 200 °C in humid air, superior to bare Ru or Pt samples. Experimental verification and theoretical calculation identified that the relative lower barriers of CB adsorption and O2 dissociation on RuPt-ALD contributed to its stronger CB adsorption and appropriate oxygen activation capacity, which were the core factors for the excellent performance under humid feed. In addition, under dry feed, the desorption ability of Cl species was also a key factor affecting the performance of Pt-based catalysts.

Electronic Modulation and Mechanistic Study of Ru-Decorated Porous Cu-Rich Cuprous Oxide for Robust Alkaline Hydrogen Oxidation and Evolution Reactions.

Rational design of high-efficiency and viable electrocatalysts is essential in overcoming the bottleneck of sluggish alkaline hydrogen oxidation/evolution reaction (HOR/HER) kinetics. In this study, a metal-organic framework-derived strategy for constructing a Pt-free catalyst with Ru clusters anchored on porous Cu-Cu2 O@C is proposed. The designed Ru/Cu-Cu2 O@C exhibits superior HOR performance, with a mass activity of 2.7 mA at 50 mV, which is about 24 times higher than that of state-of-the-art Pt/C (0.11 mA ). Significantly, Ru/Cu-Cu2 O@C also displays impressive HER performance by generating 26 mV at 10 mA cm-2 , which exceeds the majority of documented Ru-based electrocatalysts. Systematic characterization and density functional theory (DFT) calculations reveal that efficient electron transfer between Ru and Cu species results in an attenuated hydrogen binding energy (HBE) of Ru and an enhanced hydroxy binding energy (OHBE) of Cu2 O, together with an optimized H2 O adsorption energy with Cu2 O as the H2 O*-capturing site, which jointly facilitates HOR and HER kinetics.