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We uncover the origin of unique electronic structures of single-atom alloys (SAAs) by interpretable deep learning. The approach integrates tight-binding moment theory with graph neural networks to accurately describe the local electronic structure of transition and noble metal sites upon perturbation. We emphasize the complex interplay of interatomic orbital coupling and on-site orbital resonance, which shapes the d-band characteristics of an active site, shedding light on the origin of free-atom-like d-states that are often observed in SAAs involving d10 metal hosts. This theory-infused neural network approach significantly enhances our understanding of the electronic properties of single-site catalytic materials beyond traditional theories. [ABSTRACT FROM AUTHOR]

With advantages such as low cost, high stability, and ease of production, visible light photocatalytic C3N4 with a unique microscopic layered structure holds significant potential for development. However, its hydrogen production efficiency remains low due to the pronounced recombination of photo-generated charge carriers and limited surface reaction sites. Normally, the photocatalytic performance of C3N4 can be enhanced by loading noble metals with surface plasmon resonance. It is worth noting that the size of noble metal nanoparticles has a great influence on photocatalytic performance. In this study, accurate controlling of the size and distribution of Au nanoparticles was achieved on the surface of C3N4 by introducing amino groups to improve photocatalytic performance. Results show that uniformly distributed Au nanoparticles in the range of 2–6 nm can be obtained on C3N4 with a remarkable enhancement of hydrogen production efficiency, which is about 114 times the property of pure C3N4. The small-sized and uniformly distributed Au nanoparticles can provide more reaction sites and increase the separation of photo-generated charge carriers, in turn improving Au/NH3–C3N4 photocatalytic hydrogen release rate to 6.85 mmol g−1 h−1. This work offers a facile way to enhance photocatalytic performance by controlling the size of metal nanoparticles on C3N4 precisely. [ABSTRACT FROM AUTHOR]

Granular metals (GMs), consisting of metal nanoparticles separated by an insulating matrix, frequently serve as a platform for fundamental electron transport studies. However, few technologically mature devices incorporating GMs have been realized, in large part because intrinsic defects (e.g., electron trapping sites and metal/insulator interfacial defects) frequently impede electron transport, particularly in GMs that do not contain noble metals. Here, we demonstrate that such defects can be minimized in molybdenum–silicon nitride (Mo–SiNx) GMs via optimization of the sputter deposition atmosphere. For Mo–SiNx GMs deposited in a mixed Ar/N2 environment, x-ray photoemission spectroscopy shows a 40%–60% reduction of interfacial Mo-silicide defects compared to Mo–SiNx GMs sputtered in a pure Ar environment. Electron transport measurements confirm the reduced defect density; the dc conductivity improved (decreased) by 104–105 and the activation energy for variable-range hopping increased 10×. Since GMs are disordered materials, the GM nanostructure should, theoretically, support a universal power law (UPL) response; in practice, that response is generally overwhelmed by resistive (defective) transport. Here, the defect-minimized Mo–SiNx GMs display a superlinear UPL response, which we quantify as the ratio of the conductivity at 1 MHz to that at dc, Δ σ ω. Remarkably, these GMs display a Δ σ ω up to 107, a three-orders-of-magnitude improved response than previously reported for GMs. By enabling high-performance electric transport with a non-noble metal GM, this work represents an important step toward both new fundamental UPL research and scalable, mature GM device applications. [ABSTRACT FROM AUTHOR]

Thermal driven desorption of surface impurities is probed based on coupled Monte Carlo–heat flow–molecular dynamics simulations. Such adsorbates can lead to plasma formation during the operation of high-power microwave systems with various negative outcomes and so need to be curtailed. Our study attempts to obtain temperature thresholds for desorbing different surface contaminants such as C2, O2, CO, and CO2. The results show that carbon-based adsorbates on copper (chosen as an example anode material) could be ejected at a relatively modest surface temperature of 650 K. On the other hand, reactive species such as oxygen are very stable due to their large cohesive energies. Our calculations further suggest the benefit of using a platinum coating layer, as the noble metal is robust with strong resistance to oxidation. [ABSTRACT FROM AUTHOR]

It is a novel-effective process for realizing high-efficiency sensing and continuous gas monitoring by introducing precious metals into metal–oxide–semiconductors (MOSs). In this study, Ag is exploited to prepare surface functionalized SnO2 nanoparticles (NPs) and innovative xAg@SnO2/CsPbBr3, activating and catalyzing the gas sensing reactions on semiconductors. The results show that the precious metal Ag NPs promote the directional transport of carriers, thus improving the gas sensing performances. In addition, innovative xAg@SnO2/CsPbBr3 composites originated from Ag@SnO2 NPs and 3-mercaptopropionic acid treated all-inorganic perovskite CsPbBr3 are constructed to further accelerate electron transfer on heterointerfaces, enabling continuous and efficient monitoring of ethanolamine (EA) at room temperature. The sensing properties of Ag@SnO2/CsPbBr3 on various volatile organic compounds are investigated. Compared with pure CsPbBr3, the EA response of as-prepared 2Ag@SnO2/CsPbBr3 is obviously improved by about sevenfold. The response/recovery time is greatly shortened, besides the good stability. Another interesting result for xAg@SnO2/CsPbBr3 is the lower limit of detection of 44.43 ppb. The work demonstrates that Ag modification facilitates the adsorption/desorption rate and the response. Furthermore, the catalytic activation of noble metal Ag NPs and the synergistic interaction of SnO2/CsPbBr3 nano-heterojunctions promote EA sensing performances at room temperature. [ABSTRACT FROM AUTHOR]

Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (E C R). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on E C R at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in E C R upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable E C R is achieved. A higher contact voltage accelerates E C R stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches. [ABSTRACT FROM AUTHOR]

Body-centered-cubic–face-centered-cubic (bcc–fcc) multi-metallic nanoparticles (NPs) associating a single-crystal core (Fe, FeCo alloys, etc.) with a polycrystalline noble metal shell (Au, AuAg alloys, etc.) are perfectly symmetrical or more irregular, even dramatically dissymmetrical, yet presenting a good crystalline organization. Here, a combination of experimental analysis and theoretical symmetry analysis is proposed, in order to provide a unified description of the observed morphologies (Fe–Au and Fe–AuAg systems), whatever their symmetry, and predict some morphology variability in a population of NPs. First, the central role of the crystal lattice accommodation is comprehensively analyzed from the experimental Fe–AuAg system. The two possible bcc–fcc epitaxial relationships generate a core–shell interface in the shape of a truncated rhombic dodecahedron. This results in two different types of grains in the shell, which are elastically accommodated between them by an equal distribution of twins and low-angle grain boundaries, however, at the cost of internal stresses. At the same time, symmetry breaking results from two possible growth variants originating from the Nishiyama–Wasserman epitaxial relationships. The shell grains fit together in a nanopuzzle-like organization, resulting in a large number of possible arrangements distributed in 13 different point groups of symmetry, all of lower order than the core symmetry (highest order of cubic symmetry). If the variants are randomly distributed, the probability for the NP to be asymmetric (group 1) is 80%. The dissymmetrical development of the NPs is then discussed. Extending this approach to other core shapes succeeds in predicting dissymmetrical or dramatically off-centered morphologies experimentally observed in Fe–Au NPs. [ABSTRACT FROM AUTHOR]

Ultrafast luminescence in Mg was investigated in the infrared region, between 0.35 and 1.05 eV, and compared with the results for Al, using a luminescence upconversion technique. The luminescence intensity of these metals at 0.9 eV was higher than that of platinum with a similar surface roughness under the same excitation density. Although the Mg and Al are adjacent to each other in the periodic table and belong to "light metals," having similar band structures, their luminescence spectra differ significantly. Pronounced peak structures were found for Mg and these were attributed to interband transitions within the conduction bands consisting of 3s and 3p orbitals overlapped on the intraband continuum, based on density functional theory band structure calculation. This result is in contrast to the interband luminescence in noble metals (Au, Ag, and Cu) under continuous-wave blue laser excitation, where the final states have been assigned to the d bands. A comparison of the spectra of rough and specular surfaces suggested that the surface roughness is not essential for mitigating wavenumber mismatch for intraband transitions. The luminescence from light metals, which are harmless to humans, will be attractive for biomedical applications. [ABSTRACT FROM AUTHOR]

Surface property modification of catalyst support is a straightforward approach to optimize the performance of supported noble metal catalysts. In particular, oxygen vacancies and hydroxyl groups play significant roles in promoting noble metal dispersion on catalysts as well as catalytic stability. In this study, we developed a nanoflower-like TiO2-supported Pd catalyst that has a higher concentration of oxygen vacancies and surface hydroxyl groups compared to that of commercial anatase and P25 support. Notably, due to the distinctive structure of the nanoflower-like TiO2, our catalyst exhibited improved dispersion and stabilization of Pd species and the formation of abundant reactive oxygen species, thereby facilitating the activation of CO and O2 molecules. As a result, the catalyst showed remarkable efficiency in catalyzing the low-temperature CO oxidation reaction with a complete CO conversion at 80 °C and stability for over 100 h. [ABSTRACT FROM AUTHOR]

The high activity and high selectivity in the catalytic oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) under non-alkaline conditions has always been a significant challenge in the field of biomass utilization. In this work, a thermodynamically stabilized high-entropy alloy (HEA) structure with relatively low Pt content was synthesized via a simple impregnation–calcination procedure by tuning the mixing enthalpy and the Gibbs free energy of the metal-mixing system. The prepared HEA shows excellent catalytic performance in the aerobic oxidation of HMF into FDCA under base-free conditions. Experiments and DFT calculations revealed that molecular O2 can be easily activated into highly oxidative hydroxyl radicals (˙OH) in the presence of water over the HEA surface, and facilitates the oxidation of HMF to FDCA under base-free conditions. This work provides a valuable reference for similar aerobic oxidation processes in which alkaline promoters and noble metal catalysts are needed. [ABSTRACT FROM AUTHOR]

Here, we report that black photothermal materials elevate solar heating temperatures across high solar absorption and low infrared radiation. Fe3O4 nanostructure films can be heated to 350 °C under light irradiation, and this system shows effective visible-light-driven ammonia synthesis production of 3677 µg g-1 h-1 under gas-solid phase catalysis without noble metals. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry," published by The Royal Society of Chemistry. It includes various articles on topics such as uranium extraction, ligands and their complexes, metal-organic frameworks, and materials for energy storage. The journal covers a wide range of research in the field of inorganic chemistry, showcasing diverse perspectives and advancements in the scientific community. [Extracted from the article]

The enzyme-like activity of noble metal nanomaterials has been widely demonstrated. However, as an important noble metal, iridium (Ir) and its alloy nanomaterials have been less studied, particularly regarding the effect of Ir content on enzyme-like activity. Here, we demonstrated for the first time that a low Ir content can greatly improve the peroxidase-like activity of Pt-based nanozymes. When the weight percentage of Ir was 3.45% in trimetallic PtAuIr hollow nanorods (HNRs) and 2.86% in bimetallic PtIr HNRs, their specific activity increased by approximately 70% compared to their PtAu and Pt counterparts, respectively. However, a slightly higher percentage of Ir significantly diminished the enhancement effect on their specific activity. Density functional theory (DFT) calculations show that the rate-determining step (RDS) energy barrier of the nanozyme with low Ir content is lower than that of the nanozyme with slightly higher Ir content. Furthermore, we studied the kinetic properties of the PtAuIr nanozyme using TMB as the substrate. Its Michaelis–Menten constant (Km) and Vmax were 1.756 mM and 2.152 × 10−6 M s−1, respectively. Additionally, a colorimetric detection platform based on the PtAuIr nanozyme was established and applied to detect o-phenylenediamine (OPD), with a detection limit as low as 0.076 μM. This study highlights the important role of the Ir content in Pt-based nanozymes and demonstrates that PtAuIr nanozymes have potential applications in environmental detection. [ABSTRACT FROM AUTHOR]

The limited yield of H2 production has posed a significant challenge in contemporary research. To address this issue, researchers have turned to the application of surface plasmon resonance (SPR) materials in photocatalytic H2 generation. SPR, arising from collective electron oscillations, enhances light absorption and facilitates efficient separation and transfer of electron‐hole pairs in semiconductor systems, thereby boosting photocatalytic H2 production efficiency. However, existing reviews predominantly focus on SPR noble metals, neglecting non‐noble metals and SPR semiconductors. In this review, we begin by elucidating five different SPR mechanisms, covering hot electron injection, electric field enhancement, light scattering, plasmon‐induced resonant energy transfer, and photo‐thermionic effect, by which SPR enhances photocatalytic activity. Subsequently, a comprehensive overview follows, detailing the application of SPR materials‐metals, non‐noble metals, and SPR semiconductors‐in photocatalytic H2 production. Additionally, a personal perspective is offered on developing highly efficient SPR‐based photocatalysis systems for solar‐to‐H2 conversion in the future. This review aims to guide the development of next‐gen SPR‐based materials for advancing solar‐to‐fuel conversion. [ABSTRACT FROM AUTHOR]

The chemical and electronic interactions at metal/oxide heterojunctions is pivotal in determining the electronic properties of oxide devices utilized in microelectronics, catalysis, and photovoltaic systems. In this study, interfacial oxidation migrations within a model heterostructure system, consisting of a La0.7Sr0.3MnO3 film overlaid by various metallic (Ti, Al, Cu, Ag, and Au) ultrathin layers are systematically investigated. It is experimentally demonstrated that at elevated deposition temperature, the oxygen‐active ultrathin overlayers of base metals such as Ti and Al significantly derive oxygen from the underlying La0.7Sr0.3MnO3 film, inducing a perovskite to brownmillerite phase transition in the underlying functional oxide film. Conversely, no structural transitions are observed for La0.7Sr0.3MnO3 film when it is capped by noble metals (Au, Ag), which possess relative high oxidation formation energy. These observations are crucial for the development of novel crystalline and electronic architectures in metal/oxide heterostructures, offering a refined approach to modulate interfacial reactivity without compromising the functionality of oxide‐based heterojunction devices. [ABSTRACT FROM AUTHOR]

Three‐way catalysis represents a pivotal technology for converting automobile exhaust pollutants into non‐toxic gases. Substituting some noble metals with transition metals is considered a promising way to reduce catalyst costs. Herein, we have investigated the catalytic potential of different configurations of Pd−Cu catalysts prepared by impregnation (PdCu/MA), sol‐gel (PdCu‐MA), impregnation with physical mixing (Pd/Cu/MA) and sol‐gel with physical mixing (Pd/Cu‐MA) to modify the interaction of Pd/Cu and MgAl1.82Ce0.18O4 (MA) spinel in this comparative study. The different structures in these catalysts lead to different catalytic performances. PdCu/MA exhibits the best three‐way catalytic performance, which owe to the small‐sized PdCu particles with high Pd2+ content (45.3 %) and optimal interaction of Pd/Cu particles and MgAl1.82Ce0.18O4 support. Furthermore, comprehensive CO‐DRIFTS, H2‐TPR, and O2‐TPD analyses discover that the metal‐support interaction is beneficial to enhance the catalytic performance in three‐way catalysis. Overall, we demonstrated that the interaction between PdCu bimetals and support can regulate the electronic state of Pd, thereby enhancing the use and efficiency of noble metals. [ABSTRACT FROM AUTHOR]

Coupling in situ generated intermediates with other substrates/intermediates is a viable approach for diversifying product outcomes of catalytic reactions involving two or multiple reactants. Cyclohexanone oxime is a key precursor for caprolactam synthesis (the monomer of Nylon‐6), yet its current production uses unsustainable carbon sources, noble metal catalysts, and harsh conditions. Herein, we report the first work to synthesize cyclohexanone oxime through electroreduction of phenol and hydroxylamine. The Faradaic efficiency reached 69.1 % over Cu catalyst, accompanied by a corresponding cyclohexanone oxime formation rate of 82.0 g h−1 gcat−1. In addition, the conversion of phenol was up to 97.5 %. In situ characterizations, control experiments, and theoretical calculations suggested the importance of balanced activation of water, phenol, and hydroxylamine substrates on the optimal metallic Cu catalyst for achieving high‐performance cyclohexanone oxime synthesis. Besides, a tandem catalytic route for the upgrading of lignin to caprolactam has been successfully developed through the integration of thermal catalysis, electrocatalysis, and Beckmann rearrangement, which achieved the synthesis of 0.40 g of caprolactam from 4.0 g of lignin raw material. [ABSTRACT FROM AUTHOR]

Deuterium-labeled molecules play a crucial role in numerous areas, from medicinal chemistry to chemical biology, providing a unique opportunity to improve ADMET properties and study the biological fate of bioactive molecules. Herein, we present an electromigratory reductive deuteration of terminal alkynes to access a diverse array of enamides with more than 3 deuteriums incorporated per molecule, using CD3CN as a deuterium source. The reaction proceeds under mild neutral conditions, does not require precious transition metals, and shows broad substrate scope with excellent E-selectivity. We envision that this on-demand high deuterium incorporation will provide considerable opportunities in therapeutics and biological research. [ABSTRACT FROM AUTHOR]

We have developed a double-layered ferroelectric capacitor comprising a liquid-delivery metal–organic chemical vapor deposition-based Pb(Zr, Ti)O3 (PZT) lower layer and a sputter-deposited La-doped Pb(Zr, Ti)O3 (PLZT) upper layer. This structure is designed to achieve a large polarization in the stacked-type capacitor of FeRAM. Ferroelectric capacitors with noble metal electrodes, which are patterned by sputter-etching due to the difficulty of standard chemical reactive etching typically exhibit sloped sidewalls. Consequently, their polarization values, determined by the actual capacitor area, depend on their geometric shape. Our developed capacitor exhibits a 35% increase in polarization compared to an all-sputter-deposited PLZT capacitor. This improvement is due to the reduced total thickness of the developed capacitor achieved by simplifying the bottom electrode structure, which results in steeper capacitor sidewalls. Furthermore, our developed capacitor demonstrates excellent retention margin even after 3000 h of baking at 150 °C, and with a potential endurance of 1014 cycles as predicted by voltage acceleration measurements. [ABSTRACT FROM AUTHOR]

Non-invasive imaging in the near-infrared region (NIR) offers enhanced tissue penetration, reduced spontaneous fluorescence of biological tissues, and improved signal-to-noise ratio (SNR), rendering it more suitable for in vivo deep tissue imaging. In recent years, a plethora of NIR photoresponsive materials have been employed for disease diagnosis, particularly acute kidney injury (AKI). These encompass inorganic nonmetallic materials such as carbon (C), silicon (Si), phosphorus (P), and upconversion nanoparticles (UCNPs); precious metal nanoparticles like gold and silver; as well as small molecule and organic semiconductor polymer nanoparticles with near infrared responsiveness. These materials enable effective therapy triggered by NIR light and serve as valuable tools for monitoring AKI in living systems. The review provides a concise overview of the current state and pathological characteristics of AKI, followed by an exploration of the application of nanomaterials and photoresponsive nanomaterials in AKI. Finally, it presents the design challenges and prospects associated with NIR photoresponsive materials in AKI. [ABSTRACT FROM AUTHOR]

Direct formic acid fuel cells have attracted significant attention due to their low fuel crossover, high safety, and high theoretical power density among all proton‐exchange membrane fuel cells. Numerous efforts have been dedicated to studying formic acid oxidation, particularly in the fabrication of high‐performance electrocatalysts with economical utilization of Pt metal. In this work, we report a synthetic strategy to create PtAg dots supported on plate‐like Au nanoparticles and explore their applications in electrocatalytic formic acid oxidation. The highly dispersed nature of the catalytic Pt centers and the successful construction of PtAg−Au trimetallic interfaces makes the current nanostructure an ideal system to allow for a synergetic effect between Pt, Au, and Ag, leading to improved electrocatalysis. Compared with commercial Pt/C, our PtAg‐on‐Au heterogenous nanoplates exhibit superior mass activity, along with enhanced reaction kinetics and long‐term durability for FAOR in an acidic medium. Density functional theory (DFT) simulation results indicate that AgPtAu(111) exhibits a relatively high activity for HCOOH oxidation into CO2 among the various Au‐based catalysts. This work provides a viable strategy for constructing Pt‐based electrocatalysts with controlled Pt ensembles, offering insights into the development of fuel cell catalysts that make highly efficient use of costly noble metals. [ABSTRACT FROM AUTHOR]

This study focused on searching for more effective nanomaterials for environmental remediation and health protection; thus, coliform bacteria, yeast and the organic food dye sunset yellow were selected as target pollutants to be eliminated under solar light by Ag/Cr-TiO2 and Pd/Cr-TiO2. Firstly, Cr3+ was in situ incorporated into the anatase crystalline lattice by the sol-gel method; then, Ag or Pd nanoparticles were deposited on Cr-TiO2 by chemical photoreduction. The scientific challenge addressed by the development of these composites was to analyse the recovery of Cr, to be employed in photocatalyst formulation and the enhancement of the TiO2 photocatalytic activity by addition of other noble metals. By extensive characterization, it was found that after TiO2 doping with chromium, the parameters of the crystal lattice slightly increased, due to the incorporation of Cr ions into the lattice. The TiO2 band gap decreased after Cr addition, but an increase in the optical absorptions towards the visible region after noble metals deposition was also observed, which was dependent of the Ag or Pd loading. Generally, it was observed that the noble metals type is a factor that strongly influenced the effectiveness of the photocatalysts concerning each substrate studied. Thus, by using Ag(0.1%)/Cr-TiO2, the complete elimination of E. coli from samples of water coming from a highly polluted river was achieved. Pd(0.5%)/Cr-TiO2 showed the highest efficiency in the elimination of S. cerevisiae from a lab prepared strain. On the other hand, the Pd(0.1%)/Cr-TiO2 sample shows the highest dye degradation rate, achieving 92% of TOC removal after 180 min. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) are promising candidates for the electrocatalyst of hydrogen evolution reaction (HER) due to their unique properties such as cocktail electronic effect and lattice distortion effect. Herein, the ultrasmall (sub-2 nm) nanoparticles of PtRuCoNiCu HEA with uniform element distribution are highly dispersed on hierarchical N-doped carbon nanocages (hNCNC) via low-temperature thermal reduction, denoted as us-HEA/hNCNC. The optimal us-HEA/hNCNC exhibits excellent HER performance in 0.5 M H2SO4 solution, achieving an ultralow overpotential of 19 mV at 10 mA·cm−2 (without iR-compensation), high mass activity of 13.1 A·mgnoble metals−1 at −0.10 V and superb stability with a slight overpotential increase of 3 mV after 20,000 cycles of cyclic voltammetry scans, much superior to the commercial Pt/C (20 wt.%). The combined experimental and theoretical studies reveal that the Pt&Ru serve as the main active sites for HER and the CoNiCu species modify the electron density of active sites to facilitate the H* adsorption and achieve an optimum M-H binding energy. The hierarchical pore structure and N-doping of hNCNC support also play a crucial role in the enhancement of HER activity and stability. This study demonstrates an effective strategy to greatly improve the HER performance of noble metals by developing the HEAs on the unique hNCNC support. [ABSTRACT FROM AUTHOR]

The importance of the oxygen reduction reaction (ORR) in fuel cells and zinc-air batteries is self-evident, and effective catalysts could significantly improve the catalytic efficiency of ORR. Single-atom catalysts are gaining increasing interest due to their high atom efficiency and effective catalytic performance compared to other catalyst types. While the optimal loading of catalytic sites in single-atom catalysts significantly influences their catalytic efficiency. However, creating stable single-atom catalysts with high-loading remains a difficult task. Therefore, we showcase and describe the latest developments in techniques for producing single-atom catalysts with high-loadings. In addition, the performance of noble metal, non-precious metal, and diatomic catalysts in ORR processes is summarized. What's more, the key difficulties and opportunities in the sector are demonstrated by examining the synthesis techniques and evaluating the performance and structure. This review will help researchers to advance the research process of high-loading single-atom catalysts and accelerate their practical application in the field of ORR research. [ABSTRACT FROM AUTHOR]

To ensure the green and sustainable advancement of hydrogen energy, there is a critical need for the development of a cost-effective catalyst to address the sluggish kinetics of water electrolysis under alkaline conditions. An approach to achieve this is by constructing ultrathin Pt shell-structured catalysts that offer enhanced electrocatalytic hydrogen evolution reaction performance through modulation of the inner core while minimizing costs. Herein, an ultrathin Pt shell catalyst with an inner core consisting of a PtNi face-centered cubic and hexagonal-close-packed mixed-phase interface (named PtNi-mix) is synthesized through a pre-synthesis method followed by post-acid etching process. Encouragingly, the PtNi-mix catalyst only requires 12.9 mV overpotential to achieve a current density of 10 mA·cm-2 in 1 M KOH, which is much lower than that of the commercial 20 wt.% Pt/C catalyst (71.2 mV). Also, it possesses a high mass activity (7.2 A·mg-1) at an overpotential of 70 mV, which is 9 times higher than that of the commercial 20 wt.% Pt/C catalyst. Additionally, the performance of the PtNi-mix catalyst remains almost unchanged after 10,000 cyclic voltammetry tests, indicating that the catalyst exhibits excellent stability. [ABSTRACT FROM AUTHOR]

Proton-exchange-membrane fuel cells demand highly efficient catalysts for the oxygen reduction reaction, and core-shell structures are known for maximizing precious metal utilization. Here, we reported a controllable "carbon defect anchoring" strategy to prepare Pt1Ni1@Pt/C core-shell nanoparticles with an average size of ~2.6 nm on an in-situ transformed defective carbon support. The strong Pt–C interaction effectively inhibits nanoparticle migration or aggregation, even after undergoing stability tests over 70,000 potential cycles, resulting in only 1.6% degradation. The stable Pt1Ni1@Pt/C catalysts have high oxygen reduction reaction mass activity and specific activity that reach 1.424 ± 0.019 A/mgPt and 1.554 ± 0.027 mA/cmPt2 at 0.9 V, respectively, attributed to the optimal compressive strain. The experimental results are generally consistent with the theoretical predictions made by our comprehensive microkinetic model which incorporates essential kinetics and thermodynamics of oxygen reduction reaction. The consistent results obtained in our study provide compelling evidence for the high accuracy and reliability of our model. This work highlights the synergy between theory-guided catalyst design and appropriate synthetic methodologies to translate the theory into practice, offering valuable insights for future catalyst development. Efficient and stable catalysts for oxygen reduction reactions are difficult to achieve due to slow kinetics and degradation. Here, the authors use a 'carbon defect anchoring' strategy to create Pt1Ni1@Pt core-shell nanoparticles with high activity and durability. [ABSTRACT FROM AUTHOR]

Investigating mineral/melt Sn partitioning at high temperatures and pressures is a difficult task because Sn is a redox-sensitive multivalent element and easily alloys with noble metal sample capsules. To obtain accurate Sn partition coefficients between titanite, ilmenite, and granitic melts, we developed single capsule Pt or Au and double capsule Pt95Rh5 (or Au)-Re designs to avoid significant Sn loss at a controlled oxygen fugacity (fO2). With these new capsule designs, we performed piston-cylinder experiments of Sn partitioning between titanite, ilmenite, and granitic melts. The experimental P-T-fO2 conditions were 0.5–1.0 GPa, 850–1000 °C, and ~QFM+8 to ~QFM-4 (quartz-fayalite-magnetite, QFM, buffer), with fO2 controlled by the solid buffers of Ru-RuO2, Re-ReO2, Co-CoO, graphite, and Fe-FeO. The obtained mineral/melt Sn partition coefficients ( D S n m i n / m e l t ) are 0.48–184.75 for titanite and 0.03–69.45 for ilmenite at the experimental conditions. The D S n m i n / m e l t values are largely dependent on fO2, although the effects of temperature and melt composition are also observed. D S n T t n / m e l t strongly decreases with decreasing fO2, from ~46–185 at the most oxidizing conditions (Ru-RuO2 buffer), to ~2–16 at moderately oxidizing to moderately reducing conditions (Re-ReO2 to Co-CoO and graphite buffers), to < 1 at the most reducing conditions (Fe-FeO buffer). D S n I l m / m e l t exhibits a variation trend similar to D S n T t n / m e l t but is always lower than D S n T t n / m e l t at a given fO2. These D S n m i n / m e l t values can be applied to quantitatively assess the mineralization potential of granitic magmas. Using D S n T t n / m e l t , we estimate that Sn contents are ~150–400 ppm in the pre-mineralization magmas of the tin-mineralized Qitianling plutons (South China). [ABSTRACT FROM AUTHOR]

This work investigates the use of Ti6Al4V as flow field plates in PEM-based electrolyzer stacks, utilizing its good corrosion resistance and high mechanical strength. The study explores the development of durable conductive coatings on Ti6Al4V surfaces. The coated surfaces are characterized by X-ray diffraction (XRD), showing the characteristic peaks of Pt deposited and the presence of Pt, PtO2, and TiO2 after thermal oxidation. Field emission scanning electron microscopy reveals a uniform Pt coating on Ti6Al4V with a thickness of 2–3 µm. Potentiodynamic studies revealed improved corrosion resistance with a corrosion current density of 2.1 µA·cm⁻2 in Ti6Al4V-PA-AD-TO compared to Ti6Al4V. Stability under 2 V vs. SHE for 5 h in a PEM water electrolyzer anodic environment is demonstrated, along with an evaluation of performance in a PEM electrolyzer single cell. The durability of the developed coating is assessed over 100 h in a single-cell setup, offering insights into cost-effective PEM-based electrolyzer stacks. The reduction of reliance on precious metals and the enhancement of durability provide a promising method for achieving economic viability in the production of hydrogen through water electrolysis. [ABSTRACT FROM AUTHOR]

Information about the spectra of noble metal minerals obtained by Raman spectroscopy, using the example of a new copper–gold–platinum ore occurrence in the Polar Urals, is presented. For the first time, spectra of temagamite and minerals of the intermediate merenskyite–moncheite series were obtained, and some of the previously detected minerals are refined and confirmed. The prerequisites for new mineral phases of the intermediate series are noted, difficulties in using the method and the need for further development of this area of research are indicated. It is shown that the use of Raman spectroscopy, in controversial cases, complements and often clarifies the data of microprobe studies. [ABSTRACT FROM AUTHOR]

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Transition metal phosphides (TMPs) have emerged as an alternative to precious metals as efficient and low‐cost catalysts for water electrolysis. Elemental doping and morphology control are effective approaches to further improve the performance of TMPs. Herein, Fe‐doped CoP nanoframes (Fe‐CoP NFs) with specific open cage configuration were designed and synthesized. The unique nano‐framework structured Fe‐CoP material shows overpotentials of only 255 and 122 mV at 10 mA cm−2 for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively, overwhelming most transition metal phosphides. For overall water splitting, the cell voltage is 1.65 V for Fe‐CoP NFs at a current density of 10 mA cm−2, much superior to what is observed for the classical nanocubic structures. Fe‐CoP NFs show no activity degradation up to 100 h which contrasts sharply with the rapidly decaying performance of noble metal catalyst reference. The superior electrocatalytic performance of Fe‐CoP NFs due to abundant accessible active sites, reduced kinetic energy barrier, and preferable *O‐containing intermediate adsorption is demonstrated through experimental observations and theoretical calculations. Our findings could provide a potential method for the preparation of multifunctional material with hollow structures and offer more hopeful prospects for obtaining efficient earth‐abundant catalysts for water splitting. [ABSTRACT FROM AUTHOR]

Fuel cell technologies constitute a clean, reliable, highly efficient, and eco‐friendly source of alternative energy generation. However, they still require a reliable and robust catalytic system showing comparative electrochemical activity to precious metal Pt with less cost. In this work, Mn@ZnO NPs were synthesized using a hydrothermal‐assisted simple method. Several techniques including SEM, TGA, and XRD were used to confirm the material synthesis. Electrochemical properties were analyzed by using linear sweep voltammetry, chronoamperometry, and cyclic voltammetry. A higher ORR activity in terms of mass activity and current density was observed 133.9 mA/mg as compared to Pt/C (96 mA/mg) and Pd/C (67 mA/mg) under otherwise identical conditions. Mn@ZnO also exhibited excellent current density (1.913 mA cm−2), comparable to Pt/C (1.55 mA cm−2). Chronoamperometry shows stability for up to 800 s. Comparative studies were conducted in both acidic and basic mediums, with observed higher ORR activity in acidic media. [ABSTRACT FROM AUTHOR]

In the previous decade, organic aqua regia (OAR) was discovered as a mixture of pyridine and thionyl chloride that has been observed to surprisingly yet notably selectively dissolve precious metals, dissolution‐resistant gold. Given the novel combination is two common organic solvents, it has immense potential to contribute to a circular economy of metal recycling, economically and environmentally. The underlying mechanisms behind its metal dissolution and interesting properties are not well‐understood. Using both the original mixture and derivatives, the role of each OAR reagent was analyzed in the dissolution of gold to begin probing and illuminating the novel mechanism. Three mechanisms were proposed: radical based, oxidant and ligand, and Lewis acid and base. Computational means were used to propose possible mechanisms. Experiments were used to explicate the possible mechanisms. Discoveries from the original publication were used to verify assessments and suggest future areas of study for further confirmation. Based on the finding that 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) does not significantly affect the amount of gold dissolved, the radical mechanism was dismissed. Findings from experiments replacing pyridine with its derivatives disproved the likelihood of the oxidant and ligand mechanism. Finally, with the support of proton nuclear magnetic resonance (1H NMR) and other characterization techniques, the Lewis acid and base mechanism was determined to be the most probable mechanism of OAR. The mechanistic findings reported herein will pave the way for continued understanding of the mechanism to be exploited and optimized for other metals and organometallic chemistry in the recycling of metals. [ABSTRACT FROM AUTHOR]

Plasma-catalysis has attracted significant interest in recent years as an alternative for the direct upgrading of methane into higher-value products. Plasma-catalysis systems can enable the electrification of chemical processes; however, they are highly complex with many previous studies even reporting negative impacts on methane conversion. The present work focuses on the non-oxidative plasma-catalysis of pure methane in a Dielectric Barrier Discharge (DBD) reactor at atmospheric pressure and with no external heating. A range of transition and noble metals (Ni, Fe, Rh, Pt, Pd) supported on γ-Al2O3 are studied, complemented by plasma-only and support-only experiments. All reactor packings are investigated either with pure methane or co-feeding of helium or argon to assess the role of noble gases in enhancing methane activation via energy transfer mechanisms. Electrical diagnostics and charge characteristics from Lissajous plots, and electron temperature and collision rates calculations via BOLSIG+ are used to support the findings with the aim of elucidating the impact of both active metal and noble gas on the reaction pathways and activity. The optimal combination of Pd catalyst and Ar co-feeding achieves a substantial improvement over non-catalytic pure methane results, with C2+ yield rising from 30% to almost 45% at a concurrent reduction of energy cost from 2.4 to 1.7 and from 9 to 4.7 . Pd, along with Pt, further displayed the lowest coke deposition rates among all packings with overall stable product composition during testing. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting has received tremendous attention as an eco‐friendly approach to produce hydrogen. Noble metals and their oxides are commonly used as electrocatalysts to reduce activation energy barriers for hydrogen and oxygen evolution reactions in high‐performance electrodes, but their cost, scarcity, and limited stability hinder widespread adoption of electrochemical water splitting. Further advancements are therefore needed to reduce reliance on noble metals and improve the long‐term stability. Herein, solution‐processed 2D van der Waals (vdW) p–n heterostructures as an interfacial layer between catalysts and the electrode are introduced to enhance the catalytic performance. These heterostructures are formed by sequentially assembling electrochemically exfoliated black phosphorus and molybdenum disulfide nanosheets into electronic‐grade p‐ and n‐type semiconductor thin films, with the scalability extending across tens‐of‐centimeter scale areas. Benefiting from the charge distribution and built‐in electric field developed upon heterojunction formation, the vdW heterostructure interfacial layer increases both the catalytic activity and stability of commercial Pt/C and Ir/C catalysts compared to when these catalysts are directly loaded onto electrodes. Additionally, the vdW heterostructure also serves as a template for synthesizing nanostructured Pt and Ir catalysts through electrodeposition, further enhancing the catalytic performance in terms of mass activity and stability. [ABSTRACT FROM AUTHOR]

Following the Mongol invasion of China, the Yuan (1260–1368) dynasty was the first political regime to introduce a precious metal standard and deploy paper money as the sole legal tender. Drawing on a new dataset on money issues, prices, warfare, imperial grants, taxation, natural disasters, and population, we find that a silver standard initially consolidated the Chinese currency market. However, persistent fiscal pressures eventually compelled rulers to ease the monetary standard, and a fiat standard was adopted. We show that inflation was high in the early and late periods of the dynasty but remained moderate for nearly half a century. We find that military pressure, particularly civil war, generated fiscal demands that led to the over‐issuance of money. By contrast, natural disasters and imperial grants did not trigger the over‐issue of money. Warfare was much more likely to increase paper money issues under the fiat standard than during the silver standard period. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to scrutinize the safe haven benefits of 13 individual commodities for the USA and Chinese equity sectors during the financial turmoil period. Therefore, sectoral investors in the USA and China could invest in those specific commodities that provide stable returns during the health crisis and financial turmoil periods. Design/methodology/approach: The daily data spans from February 1, 2015, to July 28, 2022. The present study applies several different approaches to analyzing the data set. The author apply the cross-quantilogram (C.Q) methodology to capture the lead-lag bivariate quantile interdependence between two stationary time series variables during the bearish, bullish and normal periods. Then the study used the hedging effectiveness (HE) and conditional diversification benefits (CDB) approaches to capture the hedging and diversification benefits of commodity classes and individual commodities. Findings: The noteworthy findings of the quantilogram methodology reveal that livestock and agriculture commodities serve as better refuges as compared to the precious metals and energy index in both countries. On average, precious metals failed to serve as safe haven investments for the USA and Chinese equity market sectors. All energy commodities except soybean oil had strong comovements with China and the US equity sectors during bearish, bullish and normal periods. Lean hogs, fiddler cattle and live cattle are perfect hedging assets for both countries due to the presence of blue color at normal and bullish periods in all C.Q heat-maps. The HE table depicts that commodity indices and individual commodities failed to serve as hedging assets for the Chinese equity sectors. But commodities are semistrong hedging assets for the US equity sectors and the S&P 500 due to the average HE values being 0.7 and above. The CDB values depict that precious metals provide diversification benefits in both equity markets. Practical implications: The present study results have important implications for equity sector investors of the USA and China in suggesting particular commodity during the financial turmoil period. During the bearish market condition, risk averse equity sector investors can invest in livestock commodities and agriculture commodities, due to their relatively stable returns. In addition, policymakers can use the analysis insights to formulate policy tools and monitoring mechanisms, effectively mitigating the unfavorable effects arising from asymmetric dependence between commodities and equity sectors during the upper tail, middle and lower tail. Policymakers can suggest equity investors to invest in which commodity during extreme conditions. Originality/value: The current study has the following points of originality. First, to the best of the author's knowledge, this is the first study to investigate the individual commodities' roles as safe havens taken from all four major commodity classes. More importantly, it is also noticeable that the safe haven abilities of commodities are usually tested for the stock market, but the equity sectors are ignored. Therefore, the present study used both stock market and sectoral indices data. [ABSTRACT FROM AUTHOR]

Catalysts are widely used in research and in industrial applications to enable or to accelerate chemical reactions. One application is monopropellant thrusters for space propulsion systems, which use hydrogen peroxide (H2O2) as liquid propellant. The decomposition of liquid hydrogen peroxide into water and oxygen gas, which then finally generates the thrust, can be achieved using noble metal catalysts like platinum and iridium. In this study, iridium–platinum alloys were deposited onto ceramic pellets by a controlled magnetron sputtering process with different parameters. Selected parameters result in coated layers featuring an atomic structure of closed- and/or open-shell microstructures. The catalytic performance of these coated pellets was evaluated in laboratory experiments. The reactivity of sputtered iridium–platinum layers for the decomposition of H2O2 was found to be significantly higher with respect to layers of pure iridium coatings. This can be explained by the better reactivity of iridium–platinum alloys, combined with the active control of the surface morphology and the microstructure of the alloy coatings. [ABSTRACT FROM AUTHOR]

The article discusses the importance of recycling in the hydrogen economy, particularly focusing on the recovery of valuable raw materials like iridium and platinum from electrolyzers and fuel cells. It highlights the challenges and processes involved in recycling these materials, emphasizing the need for a circular economy approach. The article also mentions the efforts of companies like Heraeus Precious Metals in developing efficient recycling processes and collaborating with stakeholders to establish closed cycles for materials like ionomers. [Extracted from the article]

In this work, the performance of a series of noble metal catalysts supported on the SBA-16 mesoporous matrix was studied. Its activity was measured in catalytic hydrotreating (HDT) reactions, such as tetralin hydrogenation in a batch reactor. The results were adjusted with a pseudo first order equation and then, the most active catalysts were tested in a continuous flow reactor under industrial-like conditions. Noble metal catalysts were synthesized, mainly monometallic iridium and bimetallic iridium-platinum and iridium-palladium supported SBA-16. The support was also modified with aluminum to provide Bronsted and Lewis acidity to the catalysts. All the catalysts were characterized by FTIR, XRD, NMR, N2 isotherms, H2 chemisorption, TPR and XPS to be able to relate the activity with the nature of the catalyst. The catalyst modified with 0.5 wt% of Ir, 0.5 wt% of Pt and 3 wt% of Al supported over SBA-16 matrix was the most active in tetralin hydrogenation to decalins in a Batch reactor, achieving the higher kinetic constant of 0.012 min−1 and 90% of conversion to fully hydrogenated decalins at 120 min of reaction time. This catalyst also was the most active in the hydrogenation of tetralin using a continuous flow reactor obtaining the highest kinetic constant of all the catalysts tested with a value of 0.152 mol/h g cat. and achieving 90% of conversion to decalins at W/F = 150. Its greater activity was explained in terms of greater hydrogenating capacity, better dispersion of the active species, and greater resistance to deactivation thanks to the protective effect of the bimetallic alloy formed in synergy with a greater acidity of the aluminum-modified support. In this work, optimization has been achieved in the synthesis of an active, selective, contaminant-resistant catalyst with great stability. Very good results were obtained in a continuous process under conditions like to industrial ones. [ABSTRACT FROM AUTHOR]

We develop an econometric modelling framework to forecast commodity prices taking into account potentially different dynamics and linkages existing at different states of the world and using different performance measures to validate the predictions. We assess the extent to which the quality of the forecasts can be improved by entertaining different regime‐dependent threshold models considering different threshold variables. We evaluate prediction quality using both loss minimization and profit maximization measures based on directional accuracy, directional value, the ability to predict turning points, and the returns implied by a simple trading strategy. Our analysis provides overwhelming evidence that allowing for regime‐dependent dynamics leads to improvements in predictive ability for the Goldman Sachs Commodity Index, as well as for its five sub‐indices (energy, industrial metals, precious metals, agriculture, and livestock). Our results suggest the existence of a trade‐off between predictive ability based on loss and profit measures, which implies that the particular aim of the prediction exercise carried out plays a very important role in terms of defining which set of models is the best to use. [ABSTRACT FROM AUTHOR]

Developing efficient electrocatalysts for acidic electrosynthesis of hydrogen peroxide (H2O2) holds considerable significance, while the selectivity and stability of most materials are compromised under acidic conditions. Herein, we demonstrate that constructing amorphous platinum–selenium (Pt–Se) shells on crystalline Pt cores can manipulate the oxygen reduction reaction (ORR) pathway to efficiently catalyze the electrosynthesis of H2O2 in acids. The Se2‒Pt nanoparticles, with optimized shell thickness, exhibit over 95% selectivity for H2O2 production, while suppressing its decomposition. In flow cell reactor, Se2‒Pt nanoparticles maintain current density of 250 mA cm−2 for 400 h, yielding a H2O2 concentration of 113.2 g L−1 with productivity of 4160.3 mmol gcat−1 h−1 for effective organic dye degradation. The constructed amorphous Pt–Se shell leads to desirable O2 adsorption mode for increased selectivity and induces strain for optimized OOH* binding, accelerating the reaction kinetics. This selenization approach is generalizable to other noble metals for tuning 2e‒ ORR pathway. Developing efficient catalysts for acidic electrosynthesis of H2O2 is desirable, while most materials are compromised in acidic conditions. Here, the authors report that constructing amorphous Pt–Se shells on crystalline Pt cores can regulate the reaction pathway to efficiently produce H2O2 in acid. [ABSTRACT FROM AUTHOR]

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

Low-valent palladium nanoparticles are efficient species promoting catalytic activity and selectivity in a number of chemical reactions. Recently, an atom-centered cuboctahedral Pd13 motif has been characterized as a ligand-protected [Pd13(Tr)6]2+ cluster featuring a 1s2 superatomic shell structure. In this report, we describe the ligand-cluster of and endohedral-cage interaction in [Pd13(Tr)6]2+, which accounts for a favorable situation in the overall cluster. In addition, the spherical aromatic properties of the cluster were evaluated to understand the behavior of the ligand-protected Pd13 cluster core. Our results indicate a sizable interaction towards carbon-based ligands in an overall spherical aromatic cluster featuring a long-range shielding cone. Thus, [Pd13(Tr)6]2+ is rationalized as the first ligand-protected palladium cluster to date exhibiting spherical aromatic properties, serving as a stable building block for molecule-based materials or as a dopant in porous carbon materials. [ABSTRACT FROM AUTHOR]

The substitution of noble metals with cost-effective copper nanoparticles (Cu NPs) in the preparation of metal/semiconductor composite catalysts holds significant environmental and economic implications for the degradation of various organic pollutants. However, the development of highly active and stable Cu NPs catalysts has emerged as a key challenge in the progression of non-noble metal catalysts. In this study, the reducibility of glutathione (GSH) was employed to reduce Cu2+ to Cu NPs, resulting in the formation of stable Cu-GSH nanoparticles through S–H bonds. An electrostatic self-assembly strategy was used to load Cu-GSH onto WO3 nanorods, thereby designing a Cu GSH/WO3 catalytic material with highly efficient charge transport efficiency. Under visible light irradiation, 3 wt% Cu GSH/WO3 demonstrated excellent degradation performance for organic pollutants, achieving the degradation of 99.8% of Rh B and 98.6% of TC within 60 minutes. Experimental results from photoelectrochemical (PEC) and electron spin resonance (ESR) analyses indicated that Cu GSH functions as an efficient electron trap, which triggers electron flow driven by the Schottky barrier, capturing the photoexcited electrons from WO3. This greatly enhances the separation efficiency of WO3 carriers and extends the lifetime of the carriers. It is hoped that this work will provide a viable approach for the synthesis of new high-efficiency composite photocatalytic materials. [ABSTRACT FROM AUTHOR]

Nobel metal nanostructures have been widely studied owing to their excellent surface plasmon resonance (SPR) effects. In order to regulate the SPR properties and applications of noble metal nanostructures, it is critical to accurately control their morphology and composition. Gold nanorods (Au NRs) have become a research hotpot because of their anisotropic shape and tunable plasmonic properties. By designing various heterostructures and assemblies composed of Au NRs, improvements in their SPR effects and further applications can be achieved. In this study, Au NR@Au–Ag nanoframes were prepared based on Au NRs via a sacrificial template method. The combination of metal nanostructures and open nanostructures not only maintained the characteristics of each component, but also showed synergistic effects, enhancing the performance of the composite nanostructures. Experimental results showed that the nanostructures exhibited tunable SPR properties, excellent structural stability and good catalytic activity. Furthermore, a plasmon-induced electromagnetic field enhancement effect greatly enhanced the catalytic activity of the nanostructures. This work provides new ideas and approaches for the design and development of highly active nanocatalysts. [ABSTRACT FROM AUTHOR]

Constructing atomic‐scale dispersed noble metal electrocatalysts holds enormous potential toward alkaline hydrogen oxidation reactions (HOR) owing to the high intrinsic activity and atom utilization. Here, this work shows that Ir clusters anchored on different types of molybdenum carbides (Ir/α‐MoC1‐x, Ir/β‐Mo2C) with tunable electronic interactions display distinct performance in alkaline HOR. Notably, the mass activity of Ir/α‐MoC1‐x with stronger electronic interaction is roughly twice that of Ir/β‐Mo2C. Moreover, the Ir/α‐MoC1‐x has reached an impressive mass‐normalized exchange current density (j0, mass) of 320 mA mg−1metal, making the HOR properties are comparable to those recently reported excellent alkaline HOR Ir‐based electrocatalysts. Both experimental and theoretical calculations have confirmed that the strong metal‐substrate interaction of Ir/α‐MoC1‐x via interfacial Ir‐Mo bonding, leading to a significantly modulated electronic structure and optimized binding energy of H* and OH*, thereby promoting the reaction kinetics of alkaline HOR. This work highlights strong metal‐support interactions can be an effective scheme for regulating the local electronic configuration and adsorption behavior of the catalyst along with an improved intrinsic catalytic activity. [ABSTRACT FROM AUTHOR]