Mass Specific Activity Research Articles

Synergistic effects of NiPtCo/Ti0.7W0.3O2 hybrid electrocatalysts for accelerating formic acid electro-oxidation performance.

We herein report the fabrication strategy of a robust catalyst for the formic acid electro-oxidation reaction (FAOR) via combining the advantages of a TiO2-related support and the synergistic effects of NiPtCo alloy. With the predominant dehydrogenation pathway, the NiPtCo/Ti0.7W0.3O2 catalyst shows remarkable FAOR mass activity and specific activity of 0.45 A mgMetal-1 and 1.25 mA cm-2, being 3.75- and 4.81-time higher than those of the commercially available Pt/C, respectively. The as-made FAOR electrocatalyst shows superior CO-tolerance and electrocatalytic stability during long-term operation conditions due to the synergistic contributions of each component in the overall catalyst system.

Carbon-anchoring synthesis of Pt1Ni1@Pt/C core-shell catalysts for stable oxygen reduction reaction

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.

Rapid Preparation of Platinum Catalyst in Low-Temperature Molten Salt Using Microwave Method for Formic Acid Catalytic Oxidation Reaction.

In this paper, platinum nanoparticles with a size of less than 50 nm were rapidly and successfully synthesized in low-temperature molten salt using a microwave method. The morphology and structure of the product were characterized by SEM, TEM, EDX, XRD, etc. The TEM and SEM results showed that the prepared product was a nanostructure with concave and uniform size. The EDX result indicated that the product was pure Pt, and the XRD pattern showed that the diffraction peaks of the product were consistent with the standard spectrum of platinum. The obtained Pt/C nanoparticles exhibited remarkable electrochemical performance in a formic acid catalytic oxidation reaction (FAOR), with a peak mass current density of 502.00 mA·mg-1Pt and primarily following the direct catalytic oxidation pathway. In addition, in the chronoamperometry test, after 24 h, the mass-specific activity value of the Pt concave NPs/C catalyst (10.91 mA·mg-1Pt) was approximately 4.5 times that of Pt/C (JM) (2.35 mA·mg-1Pt). The Pt/C NPs exhibited much higher formic acid catalytic activity and stability than commercial Pt/C. The microwave method can be extended to the preparation of platinum-based alloys as well as other catalysts.

Surface‐Engineered Pt‐Ni(111) Nanocatalysts for Boosting Their ORR Performance via Thermal Treatment

AbstractThe electrochemical oxygen reduction reaction (ORR) is critical for fuel cell application, and modifying surface structures of electrocatalysts has proven effective in improving their catalytic performances. In this study, we investigated surface‐engineered Pt−Ni nano‐octahedra subjected to annealing in various atmospheres. All octahedral nanocrystals retained their Pt−Ni {111} facets at an elevated temperature following the annealing treatments. Air annealing led to the formation of nickel‐rich shells on the Pt−Ni surface. In contrast, hydrogen (H₂) as a reducing gas facilitated the reduction of surface Ni species, incorporating them into the Pt−Ni bulk alloy, which resulted in superior mass activity and specific activity for ORR‐approximately 2.4 and 2.3 times as high as those from the unmodified counterpart, respectively. After 20,000 potential cycles, the H₂/Ar‐annealed Pt−Ni nano‐octahedra maintained a mass activity of 3.92 A/ , surpassing the initial mass activity of the unannealed counterparts (2.95 A/ ). These findings demonstrate a viable approach for tailoring catalyst surfaces to enhance performance in various energy storage and conversion applications.

Embedding Single Pd Atoms on NiGa Intermetallic Surfaces for Efficient and Selective Alkyne Hydrogenation.

Catalytic removal of alkynes is essential in industry for producing polymer-grade alkenes from steam cracking processes. Non-noble Ni-based catalysts hold promise as effective alternatives to industrial Pd-based catalysts but suffer from low activity. Here we report embedding of single-atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well-defined synthesis strategy to design Pd1-NiGa catalyst for alkyne semi-hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96 % than the state-of-the-art catalysts under industry-relevant conditions. Integrated experimental and computational studies reveal that the single-atom Pd synergizes with the neighbouring Ni sites to facilitate the σ-adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single-atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi-hydrogenation, providing an effective strategy for stimulating low active Ni-based catalysts for other selective hydrogenations in industry.

Construction of Multiphase Concave Tetrahedral PdInMo Nanocatalyst for Enhanced Alcohol Oxidation

AbstractHeterogeneous palladium‐based catalysts show excellent catalytic properties for electrocatalytic oxidation of alcohols, but the construction of such heterogeneous catalysts is a challenge. Here, a multiphase tetrahedral PdInMo nanocatalyst is prepared by a one‐pot reaction method. And the multiphase tetrahedral PdInMo nanocatalyst consists of a face‐centered cubic structure and an intermetallic structure. Due to the oxygen affinity of indium and molybdenum atoms, the interface defects of internal multiphase structure, and intermetallic structure, the multiphase concave tetrahedral PdInMo nanocatalyst shows enhanced catalytic efficiency in the electrocatalytic oxidation reaction of methanol and ethanol. Compared with commercial Pd/C catalysts, PdIn0.117Mo0.037 nanocatalyst has the best mass activity and specific activity. In electrocatalysis of methanol oxidation, the mass activity (2205.57 mA mgPd−1) and specific activity (6.67 mA cm−2) are 4.81 and 3.40 times than that of a commercial Pd/C nanocatalyst (458.5 mA mgPd−1, 1.96 mA cm−2), respectively. In the electrocatalysis of ethanol oxidation, the mass activity (2668.49 mA mgPd−1) and specific activity (8.11 mA cm−2) are 4.06 and 3.14 times than that of the commercial Pd/C nanocatalyst (655.83 mA mgPd−1, 2.58 mA cm−2), respectively. This study provides a reference for the design of highly efficient palladium catalysts for alcohol oxidation.

Prompt template-free synthesis of porous PtPb sponge-like nanostructure for electro-oxidation of methanol and carbon monoxide

Porous Pt-based alloys entail earth-abundant and low-cost metal, not only contribute to the rational consumption of expensive and rare Pt metal but also the enhancement of its activity towards the methanol electro-oxidation reaction (MEOR). Herein, a porous sponge-like PtPb alloy was synthesized by using the ice-reduction method driven by the coalescence growth mechanism under the intensive reduction power of borohydride. The presented PtPb sponge nanostructure was prepared using a facile, one-step method without heating or surfactants. Meanwhile, PtPb had a sponge-like shape with accessible active sites, a high surface area, abundant pore volume (0.05 cm3/g), pore size (2–20 nm), Pb loading (13.0 at.%), and an upshifted d-band center of Pt. These inimitable structural and compositional merits endow the electro-oxidation of methanol with a higher mass (specific) activity of 0.907 mA/µgPt (5.7 mA/cm2) compared to those of Pt sponge-like nanostructure and Pt/C catalyst by 1.47 (1.35) and 1.72 (8.51) times, respectively, besides higher durability. Moreover, PtPb had higher activity and durability towards the electro-oxidation of carbon monoxide (CO) than Pt and Pt/C. The proposed study may provide new insights into the simple synthesis of a Pt-based alloy for the electrocatalytic oxidation of small organic molecules.

Machine Learning‐Aided Discovery of Low‐Pt High Entropy Intermetallic Compounds for Electrochemical Oxygen Reduction Reaction

Advancing the design of cathode catalysts to significantly maximize platinum utilization and augment the longevity has emerged as a formidable challenge in the field of fuel cells. Herein, we rationally design a high entropy intermetallic compound (HEIC, Pt(FeCoNiCu)3) for catalyzing oxygen reduction reaction (ORR) by an efficient machine learning stategy, where crystal graph convolutional neural networks are employed to expedite the multicomponent design. Based on a dataset generated from first‐principles calculations, the model can achieve a high prediction accuracy with mean absolute errors of 0.003 for surface strain and 0.011 eV atom‐1 for formation energy. In addition, we identify two chemical features (atomic size difference and mixing enthalpy) as new descriptors to explore advanced ORR catalysts. The carbon supported Pt(FeCoNiCu)3 catalyst with small particle size is successfully synthesized by a freeze‐drying‐annealing technology, and exhibits ultrahigh mass activity (4.09 A mgPt‐1) and specific activity (7.92 mA cm‐2). Meanwhile, The catalyst also shows significantly enhanced electrochemical stability which can be ascribed to the sluggish difussion effect in the HEIC structure. Beyond offering a promising low‐Pt electrocatalysts for fuel cell cathode, this work offers a new paradigm to rationally design advanced catalysts for energy storage and conversion devices.

Machine Learning-Aided Discovery of Low-Pt High Entropy Intermetallic Compounds for Electrochemical Oxygen Reduction Reaction.

Advancing the design of cathode catalysts to significantly maximize platinum utilization and augment the longevity has emerged as a formidable challenge in the field of fuel cells. Herein, we rationally design a high entropy intermetallic compound (HEIC, Pt(FeCoNiCu)3) for catalyzing oxygen reduction reaction (ORR) by an efficient machine learning stategy, where crystal graph convolutional neural networks are employed to expedite the multicomponent design. Based on a dataset generated from first-principles calculations, the model can achieve a high prediction accuracy with mean absolute errors of 0.003 for surface strain and 0.011 eV atom-1 for formation energy. In addition, we identify two chemical features (atomic size difference and mixing enthalpy) as new descriptors to explore advanced ORR catalysts. The carbon supported Pt(FeCoNiCu)3 catalyst with small particle size is successfully synthesized by a freeze-drying-annealing technology, and exhibits ultrahigh mass activity (4.09 A mgPt-1) and specific activity (7.92 mA cm-2). Meanwhile, The catalyst also shows significantly enhanced electrochemical stability which can be ascribed to the sluggish difussion effect in the HEIC structure. Beyond offering a promising low-Pt electrocatalysts for fuel cell cathode, this work offers a new paradigm to rationally design advanced catalysts for energy storage and conversion devices.

High Fe-Loading Single-Atom Catalyst Boosts ROS Production by Density Effect for Efficient Antibacterial Therapy

HighlightsFe single-atom catalysts (h3-FNCs) with high loading, high catalytic activity and high stability were synthesized via a method capable of increasing both the metal loading and mass-specific activity by exchanging zinc with iron.The “density effect,” derived from the sufficiently high density of active sites, has been discovered for the first time, leading to a significant alteration in the intrinsic activity of single-atom metal sites.The superior oxidase-like catalytic performance of h3-FNCs ensures highly effective bacterial eradication.

Efficient catalysis for acidic methanol oxidation: Exploration of a Low-Platinum quaternary alloy catalyst via a Two-Step method

The quest for platinum-based catalysts with enhanced catalytic efficacy and durability during the methanol oxidation reaction (MOR) has been a focal point in energy conversion science. Traditional platinum-based catalysts are often constrained by their high platinum content, which escalates economic costs and complicates experimental protocols. In this study, we introduce a low-platinum-loaded catalyst synthesized via a two-step method, which incorporates a four-component alloy. This innovative approach significantly reduces platinum content while maintaining superior catalytic performance through precise control over the alloy’s composition and structure. The two-step synthesis methodology streamlines the conventional multi-step processes, enhancing the catalyst preparation’s efficiency and reproducibility. The resulting PtCoSnCu/N-C alloy catalyst exhibits remarkable catalytic activity in methanol solution, with mass activity and specific activity that are 9.73 and 9.75 times higher, respectively, than those of commercial platinum on carbon (Pt/C) catalysts. Notably, the optimized PtCoSnCu/N-C alloy catalyst demonstrates exceptional long-term stability, outperforming Pt/C in aging and extended stability tests. Density functional theory (DFT) calculations elucidate the optimization of the electronic structure and the synergistic effect of surface atoms in the PtCoSnCu/N-C catalyst, which mitigates the adsorption energy of CO molecules and enhances the utilization rate of active sites during the oxidation process. This research presents a paradigm-shifting low-platinum catalyst strategy for methanol fuel cells, establishing a theoretical foundation for catalyst design and optimization.

Building robust copper nanostructures via carbon coating derived from polydopamine for oxygen reduction reaction

This study explores the synthesis and electrocatalytic performance of copper-nitrogen-carbon composites formed by Cu single atoms/clusters embedded in nitrogen-doped carbon with Cu/Cu2O nanoparticles (Cu-X-NC) for the oxygen reduction reaction (ORR). The catalysts were synthesized using polydopamine as a carbon and nitrogen source via the solvothermal carbonization (STC) method, followed by pyrolysis and acid washing. The effect of solvothermal carbonization temperature (120, 150, and 180 ºC) on the structure and ORR activity was investigated. The physicochemical characterization showed that higher STC temperatures reduced the size of copper crystallites, slightly increased the formation of copper(I) oxide, and led to the creation of well-dispersed copper single atoms/clusters at 150°C. This optimal dispersion enhances the interaction between the copper single atoms and the reactants, leading to faster ORR kinetics, as demonstrated by the lower charge transfer resistance values in electrochemical impedance spectroscopy measurements. Additionally, the balance between micropore and mesopore structures at this temperature facilitates efficient mass transport, which is critical for achieving higher ORR activity. Moreover, accelerated stability tests showed excellent durability for Cu-150-NC, with negligible loss in onset potential after 10,000 cycles. The solvothermal process significantly increased the electrochemically active surface area (ECSA), with Cu-150-NC displaying the highest specific activity and mass activity per gram of copper, indicating superior performance. Overall, these findings underscore the importance of synthesis optimization and provide valuable insights for designing eco-friendly and high-performance copper catalysts for fuel cell applications.

Rutile-structured high-entropy oxyfluorides: A platform for oxygen evolution catalysis

High-entropy (HE) design provides ample opportunities for accessing catalysts with unique physiochemical properties for advanced energy and environmental applications. Although a variety of multi-cationic high-entropy materials (HEMs) have been identified, HEMs consisted of multiple cationic and anionic elements are still limited. Herein, we present the design and synthesis of a series of rutile-structured high-entropy oxyfluorides (HEOFs), including [RuO2]x[MgMnZnCoF2]y, [MnO2]x[MgMnZnCoF2]y, [MoO2]x[MgMnZnCoF2]y, [SnO2]x[MgMnZnCoF2]y and [TiO2]x[MgMnZnCoF2]y (x:y = 3:1, 2:1, 1:1). All the HEOFs are obtained through mechanochemical alloying rutile-structured oxide and fluoride precursors and the HEOFs inherit the crystal structures of the skeleton oxides. Moreover, the HEOFs exhibit enhanced electrocatalytic oxygen evolution reaction (OER) activity than the corresponding one-element precursors. Typically, the best-performed HEOF [RuO2]3[MgMnZnCoF2]1 catalyst requires an overpotential of 240 mV to achieve a current density of 10 mA cm−2, which is lower than RuO2 (291 mV). More impressively, the specific mass activity of [RuO2]3[MgMnZnCoF2]1 is 537.1 A gRu−1 at 1.55 V (vs RHE), which is ca. 7.6 times that of RuO2 (70.5 A gRu−1). The enhanced electrocatalytic OER performance obtained on [RuO2]3[MgMnZnCoF2]1 is ascribed to the contribution of the different cationic and anionic elements that modulates the electronic structures of the pristine RuO2, which facilitates efficient OER kinetics. This work demonstrates the efficacy of high-entropy design towards approaching excellent catalysts for enhanced electrocatalysis.

Platinum/Platinum Sulfide on Sulfur-Doped Carbon Nanosheets with Multiple Interfaces toward High Hydrogen Evolution Activity.

Platinum (Pt)-based materials are among the most competitive electrocatalysts for the hydrogen evolution reaction (HER) due to suitable hydrogen adsorption energy. Due to the rarity of Pt, it is desirable to develop cost-effective Pt-based electrocatalysts with low Pt loading. Herein, Pt/PtS electrocatalysts on S-doped carbon nanofilms (PPS/C) have been successfully fabricated through a precursor reduction route with a complex of Pt and 1-dodecanethiol (1-DDT) as the precursor. The PPS/C achieved at 400 °C (PPS/C-400) exhibits excellent HER performances with an ultralow overpotential of 41.3 mV, a low Tafel slope of 43.1 mV dec-1 at a current density of 10 mA cm-2, and a long-term stability of 10 h, superior to many recently reported Pt-based HER electrocatalysts. More importantly, PPS/C-400 shows a high mass-specific activity of 0.362 A mgPt-1 at 30 mV, which is 1.88 times of that of commercial 20% Pt/C (0.193 A mgPt-1). The introduction of sulfur leads to the formation of PtS, which not only reduces the content of Pt but also realizes the interface regulation of Pt/PtS, as well as the doping of carbon. Both regulations make the resulting catalyst have abundant active centers and rapid electron transfer/transport, which is conducive to balancing the adsorption and resolution of intermediate products, and finally achieving great mass-specific activity and stability. The research work may provide ideas for designing effective Pt-based multi-interface electrocatalysts.

Extremely Active and Robust Ir−Mn Dual‐Atom Electrocatalyst for Oxygen Evolution Reaction by Oxygen‐Oxygen Radical Coupling Mechanism

AbstractA novel Ir−Mn dual‐atom electrocatalyst is synthesized by a facile ion‐exchange method by incorporating Ir in SrMnO3, which yields an extremely high activity and stability for the oxygen evolution reaction (OER). The ion exchange process occurs in a self‐limitation way, which favors the formation of Ir−Mn dual‐atom in the IrMnO9 unit. The incorporation of Ir modulates the electronic structure of both Ir and Mn, thereby resulting in a shorter distance of the Ir−Mn dual‐atom (2.41 Å) than the Mn−Mn dual‐atom (2.49 Å). The modulated Ir−Mn dual‐atom enables the same spin direction O (↑) of the adsorbed *O intermediates, thus facilitating the direct coupling of the two adsorbed *O intermediates to release O2 via the oxygen‐oxygen radical coupling mechanism. Electrochemical tests reveal that the Ir‐SrMnO3 exhibits a superior OER's activity with a low overpotential of 207 mV at 10 mA cm−2 and achieves a mass specific activity of 1100 A gIr−1 at 1.5 V. The proton‐exchange‐membrane water electrolyzer with the Ir‐SrMnO3 catalyst exhibits a low electrolysis voltage of 1.63 V at 1.0 A cm−2 and a stable 2000‐h operation with a decay of only 15 μV h−1 at 0.5 A cm−2.

Ultrathin ternary PtNiRu nanowires for enhanced oxygen reduction and methanol oxidation catalysis via d-band center regulation

Direct methanol fuel cells rely on the efficiency of their anode/cathode electrocatalysts to facilitate the methanol oxidation reaction and oxygen reduction reaction, respectively. Platinum-based nanocatalysts are at the forefront due to their superior catalytic properties. However, the high-cost, scarcity, and low CO tolerance of platinum pose challenges for the scalable application of DMFCs. Herein, we report novel ultrathin ternary PtNiRu alloy nanowires to improve Pt utilization and CO tolerance. These novel electrocatalysts incorporate the oxophilic metal Ru into ultrathin PtNi nanowires, aiming to enhance the intrinsic activity of platinum while leveraging the long-term durability and high utilization efficiency provided by the bimetallic synergistic effect. The PtNiRu NWs significantly enhance both mass activity and specific activity for ORR, performing about 6.9 times and 3.9 times better than commercial Pt/C, respectively. After a rigorous durability test of 10,000 cycles, the PtNiRu NWs only exhibited a 25.2 % loss in mass activity. Additionally, for MOR, the MA and SA of PtNiRu NWs exceed that of Pt/C catalyst by 4.30 and 2.72 times, respectively, and exhibit exceptional resistance to CO poisoning. Theoretical insights from density functional theory calculations suggest that the introduction of Ru modulates the d-band center of the surface Pt atoms, which contributes to decreased binding strength of oxygenated species and an elevated dissolution potential, substantiating the enhanced performance metrics, and the durability enhancement stems from the stronger PtM bonds than those in PtNiRu NWs resulted from PtRu covalent interactions. These findings not only provide a new perspective on platinum-based nanocatalysts but also significantly advance the quest for more efficient and durable electrocatalysts for DMFCs, representing a substantial stride in fuel cell technology.

Tuning d-band center of Pt via Pt-Pt5La heterostructure interface as efficient and stable electrocatalyst for oxygen reduction and methanol oxidation reactions in DMFCs

Developing Pt-based electrocatalysts with superior activity and durability is essential for direct methanol fuel cells (DMFCs), and regulating the interfacial electronic interaction for Pt-based composites can significantly modulate the electrocatalytic performances. Herein, the Pt-Pt5La/C heterostructure catalyst was developed to enhance the catalytic property towards oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR). Experimental analyses and theoretical calculations demonstrated the electron redistribution at the interface and reduction of the d-band center of Pt for this unique Pt-Pt5La/C heterostructure. As the results, Pt-Pt5La/C exhibited 5.0- and 6.4-times higher mass activity and specific activity towards alkaline ORR compared to Pt/C, and the excellent electrocatalytic MOR performance due to the interfacial interaction. These superior electrocatalytic property promoted Pt-Pt5La/C as the bifunctional catalyst for DMFC application with outstanding power density and durability. Consequently, this work proposed a novel interfacial regulation strategy for designing Pt-rare earth (RE) alloy heterostructures and their reliable operation of DMFCs.

N-doped carbon confined ternary Pt2NiCo intermetallics for efficient oxygen reduction reaction

Developing high performance electrocatalysts for the cathodic oxygen reduction reaction (ORR) is essential for the widespread application of fuel cells. Herein, a promising Pt2NiCo atomic ordered ternary intermetallic compound with N-doped carbon layer coating (o-Pt2NiCo@NC) has been synthesized via a facile method and applied in acidic ORR. The confinement effect provided by the carbon layer not only inhibits the agglomeration and sintering of intermetallic nanoparticles during high temperature process but also provides adequate protection for the nanoparticles, mitigating the aggregation, detachment and poisoning of nanoparticles during the electrochemical process. As a result, the o-Pt2NiCo@NC demonstrates a mass activity (MA) and specific activity (SA) of 0.65 A/mgPt and 1.41 mA/cmPt2 in 0.1 mol/L HClO4, respectively. In addition, after 30,000 potential cycles from 0.6 V to 1.0 V, the MA of o-Pt2NiCo@NC shows much lower decrease than the disordered Pt2NiCo alloy and Pt/C. Even cycling at high potential cycles of 1.5 V for 10,000 cycles, the MA still retains ∼70%, demonstrating superior long-term durability. Furthermore, the o-Pt2NiCo@NC also exhibits strong tolerance to CO, SOx, and POx molecules in toxicity tolerance tests. The strategy in this work provides a novel insight for the development of ORR catalysts with high catalytic activity, durability and toxicity tolerance.

Embedding Single Pd Atoms on NiGa Intermetallic Surfaces for Efficient and Selective Alkyne Hydrogenation

AbstractCatalytic removal of alkynes is essential in industry for producing polymer‐grade alkenes from steam cracking processes. Non‐noble Ni‐based catalysts hold promise as effective alternatives to industrial Pd‐based catalysts but suffer from low activity. Here we report embedding of single‐atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well‐defined synthesis strategy to design Pd1−NiGa catalyst for alkyne semi‐hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96 % than the state‐of‐the‐art catalysts under industry‐relevant conditions. Integrated experimental and computational studies reveal that the single‐atom Pd synergizes with the neighbouring Ni sites to facilitate the σ‐adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single‐atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi‐hydrogenation, providing an effective strategy for stimulating low active Ni‐based catalysts for other selective hydrogenations in industry.

Kinetics-Driven Crystal Facet Evolution Mechanism of Atomically Ordered Intermetallic PtFe Nanocubes toward Electrochemical Catalysis.

Crystal structure engineering in nanoparticles has been regarded as a vital method in catalyst development and design. Herein, PtFe nanocubes, manufactured with ordered PtFe intermetallic structure and a desired facet of {202}, have been successfully prepared via the combination of selective deposition strategy and spatial barrier effect. In-situ X-ray photoelectron spectroscopy found that the growth of the high-index facet and formation of the nanocube for o-PtFe-202 materials arise from the surface Fe2+ modification stabilized effect and the selective deposition of Cl-, respectively. Moreover, density functional theory calculations and X-ray adsorption spectroscopies further proved that the improved oxygen reduction reaction activity and stability of o-PtFe-202 mainly originate from the synergistic effect of the desired high-index facet, ordered crystal structure, and resulting optimal d-band center of Pt. As expected, the o-PtFe-202 exhibits excellent mass activity (2.48 mA·ugPt-1) and specific activity (7.78 mA·cm-2), with only a 7.3% decrease in mass activity after 30 000 cycles.