Hybrid Catalyst Research Articles

Bridged Pt-OH-Mn Mediator in N-coordinated Mn Single Atoms and Pt Nanoparticles for Electrochemical Biomolecule Oxidation and Discrimination.

The rational design of efficient catalysts for uric acid (UA) electrooxidation, as well as the establishment of structure-activity relationships, remains a critical bottleneck in the field of electrochemical sensing. To address these challenges, herein, a hybrid catalyst that integrates carbon-supported Pt nanoparticles and nitrogen-coordinated Mn single atoms (PtNPs/MnNC) is developed. The metal-metal interaction during annealing affords the construction of metallic-bonded Pt-Mn pairs between PtNPs and Mn single atoms, facilitating the electron transfer from PtNPs to the support and thereby optimizing the electronic structure of catalysts. More importantly, experiments and theoretical calculations provide visual proof for the 'incipient hydrous oxide adatom mediator' mechanism for UA oxidation. The Pt-Mn pairs first adsorb OH* to construct the bridged Pt-OH-Mn mediators to serve as a highly active intermediate for N-H bond dissociation and proton transfer. Benefiting from the unique electronic and geometric structure of the catalytic center and reactive intermediates, PtNPs/MnNC exhibits superior electrooxidation performance. The electrochemical sensor based on PtNPs/MnNC enables sensitive detection and discrimination of UA and dopamine in serum samples. This work offers new insights into the construction of novel electrocatalysts for sensitive sensing platforms.

Bridged Pt−OH−Mn Mediator in N‐coordinated Mn Single Atoms and Pt Nanoparticles for Electrochemical Biomolecule Oxidation and Discrimination

AbstractThe rational design of efficient catalysts for uric acid (UA) electrooxidation, as well as the establishment of structure‐activity relationships, remains a critical bottleneck in the field of electrochemical sensing. To address these challenges, herein, a hybrid catalyst that integrates carbon‐supported Pt nanoparticles and nitrogen‐coordinated Mn single atoms (PtNPs/MnNC) is developed. The metal‐metal interaction during annealing affords the construction of metallic‐bonded Pt−Mn pairs between PtNPs and Mn single atoms, facilitating the electron transfer from PtNPs to the support and thereby optimizing the electronic structure of catalysts. More importantly, experiments and theoretical calculations provide visual proof for the ‘incipient hydrous oxide adatom mediator’ mechanism for UA oxidation. The Pt−Mn pairs first adsorb OH* to construct the bridged Pt−OH−Mn mediators to serve as a highly active intermediate for N−H bond dissociation and proton transfer. Benefiting from the unique electronic and geometric structure of the catalytic center and reactive intermediates, PtNPs/MnNC exhibits superior electrooxidation performance. The electrochemical sensor based on PtNPs/MnNC enables sensitive detection and discrimination of UA and dopamine in serum samples. This work offers new insights into the construction of novel electrocatalysts for sensitive sensing platforms.

Graphitic carbon nitride-PTD hybrid catalyst for efficient photocatalytic oxidative coupling of arylamine for the production of azoaromatic under visible light

Oxidative coupling of amine derivatives to selectively synthesize pharmaceutical materials has been realized via photocatalysis. Herein we report on the fabrication and development of a graphitic carbon nitride (G) based visible light active photocatalyst (G-PTD), which is melamine converted graphitic carbon nitride(G) covalently integrated to a light harvesting perylene tetracarboxylic dianhydride (PTD) molecule. The synthesized photocatalyst has various functions in a highly active manner leading to high yield of newly generated azoaromatic compound. The current research endeavour highlights on the fabrication and utilization of a graphitic carbon nitride based photocatalyst for direct oxidative coupling of arylamines.

Epitaxial growth of highly atomically ordered Pt-Fe nanoparticles from carbon nanotube bundles as durable oxygen reduction electrocatalysts

Intermetallic Pt-based nanoparticles have displayed excellent activity for the oxygen reduction reaction (ORR) in fuel cells. However, it remains a great challenge to synthesize highly atomically ordered Pt-based nanoparticle catalysts because the formation of an atomically ordered structure usually requires high-temperature annealing accompanied by grain sintering. Here we report the direct epitaxial growth of well-aligned, highly atomically ordered Pt3Fe and PtFe nanoparticles (<5 nm) on single-walled carbon nanotube (SWCNT) bundles films. The long-range periodically symmetric van der Waals (vdW) interactions between SWCNT bundles and Pt-Fe nanoparticles play an important role in promoting not only the alignment ordering of inter-nanoparticles but also the atomic ordering of intra-nanoparticles. The ordered Pt3Fe/SWCNT catalyst showed enhanced ORR catalytic performance of 2.3-fold higher mass activity and 3.1-fold higher specific activity than commercial Pt/C. Moreover, the formation of an interlocked interface and strong vdW interaction endow the Pt-Fe/SWCNT catalysts with extreme long-term stability in potential cycling and excellent anti-thermal sintering ability.

N-doped MOF-lignin hybrid catalyst for highly selective hydrodeoxygenation of lignin-derived phenols

Upgrading of lignin-derived bio-oil to value-added biofuel was of great significance for efficient utilization of renewable resources and reducing the use of fossil fuels. Hydrodeoxygenation (HDO) was considered to be a promising technology for the conversion of lignin-derived bio-oil. Herein, we reported a novel method for the preparation of lignin-MOF derived N-doped catalysts, which was then successfully introduced into the upgrading of lignin-derived phenols and lignin depolymerization. All catalysts were well characterized and Co/CN-0.5–750 exhibited excellent performance during the catalytic HDO process. The optimized catalyst demonstrated highly efficient active hydrogen generation from isopropanol. Moreover, it could afford the best vanillin (VAN) conversion (100 %) and highest 2-Methoxy-4-methylphenol (MMP) yield (92 %) under the mild reaction conditions (180 °C, 0.5 MPa nitrogen, 2 h). It was confirmed that the excellent performance was related to nitrogen doping. This study could provide some useful insights for the hydrodeoxygenation of lignin and its derivative.

Low-temperature dry reforming using high entropy alloy (Co-Fe-Ga-Ni-Zn)-cerium oxide (CeO2) hybrid nanostructure

Utilization of carbon dioxide into green energy is one of the possible solutions to clean the environment. Among several possible methods, Dry reforming of methane (DRM) reaction is a simple and scalable way to convert large amounts of carbon dioxide into syngas (carbon monoxide and hydrogen). Stability is an issue in DRM as it is an endothermic reaction that results in carbon poisoning. Here, we demonstrate a high entropy alloy/CeO2 hybrid, an active and stable catalyst for DRM. The hybrid catalyst works at the lowest possible temperature i.e. 700 °C with a high H2/CO ratio along with high stability and conversion. The experimentally obtained H2/CO ratio matches with the theoretical calculated value which implies minimum side reactions. The hybrid catalyst outperforms the majority of the state of the art catalysts reported in literature. The DFT simulation and transient mechanistic study show that the hybrid catalyst results in an exothermic methane partial oxidation step due to the involvement of lattice oxygen. The current work can be utilized to clean the environment and produce highly energy-efficient fuel for green energy.

First principles energetic span analysis of the activity of transition metal catalysts for N2O decomposition: The reversal of descriptor roles in the presence of NO

The utilization of NH3 combustion faces a significant hurdle in mitigating N2O emissions, a potent greenhouse gas. Current deNOx technologies struggle to effectively decompose N2O, especially under practical conditions due to inhibitory effects from exhaust stream components like O2, NOx, and H2O. This study employs first principles investigations to analyze N2O decomposition activity on precious (Ru, Rh), non-precious (Cu, Ni), and hybrid (Ru/Cu, Rh/Cu, Ru/Ni, Rh/Ni) catalysts. Many new Brønsted-Evans-Polanyi relations are established, enabling mechanistic analysis via the Energetic Span Model. The analyses reveal opportunities for enhancing catalytic activity by exploiting weak correlations between intermediates’ free energies. The model captures the inhibitory effects of surface-adsorbed NO on the N2O decomposition activity, aligning well with experimental observations and catalytic trends. The strong binding energy of adsorbed N2/N2O and O adatom is found to be a key descriptor of activity. It is found to aid the catalytic activity in the presence of NO but becomes limiting in its absence.

Capillary-driven microchip integrated with nickel phosphide hybrid-modified electrode for the electrochemical detection of glucose

BackgroundTransition metal phosphides with properties similar to platinum metal have received increasing attention for the non-enzymatic detection of glucose. However, the requirement of highly corrosive reagent during sample pretreatment would impose a potential risk to the human body, limiting their practical applications. ResultsIn this study, we report a self-powered microfluidic device for the non-enzymatic detection of glucose using nickel phosphide (Ni2P) hybrid as the catalyst. The Ni2P hybrid is synthesized by pyrolysis of metal-organic framework (MOF)-based precursor and in-situ phosphating process, showing two linear detection ranges (1 μM–1 mM, 1 mM–6 mM) toward glucose with the detection limit of 0.32 μM. The good performance of Ni2P hybrid for glucose is attributed to the synergistic effect of Ni2P active sites and N-doped porous carbon matrix. The microchip is integrated with a NaOH-loaded paper pad and a capillary-based micropump, enabling the automatic NaOH redissolution and delivery of sample solution into the detection chamber. Under the optimized condition, the Ni2P hybrid-based microchip realized the detection of glucose in a user-friendly way. Besides, the feasibility of using this microchip for glucose detection in real serum samples has also been validated. SignificanceThis article presents a facile fabrication method utilizing a MOF template to synthesize a Ni2P hybrid catalyst. By leveraging the synergy between the Ni2P active sites and the N-doped carbon matrix, an exceptional electrochemical detection performance for glucose has been achieved. Additionally, a self-powered chip device has been developed for convenient glucose detection based on the pre-established high pH environment on the chip.

Impact of POM's coordination mode and Mo-hybrid constituents on the binding, stability, and catalytic properties of hybrid (pre)catalysts.

The assembly of MoVIO2 2+ and methoxy-substituted salicylaldehyde nicotinoyl hydrazone ligands afforded two classes of hybrid polyoxometalates (POMs). In the Class I architectures, [MoO2(HL1-3)(D)]2[Mo6O19]·xCH3COCH3 (D = CH3COCH3 or H2O, x = 0 or 2, and L1-3 = ligands bearing the OMe group at position 3, 4 and 5, respectively), the main driving force for self-assembly is the electrostatic interaction between the components. Class II architectures are composed of a POM anion covalently linked to two Mo-complex units through the terminal Ot or bridging μ2-OPOM oxygen atoms, as found in Lindqvist-based hybrids [{MoO2(HL1-3)}2Mo6O19]·xCH3CN (x = 0 or 2) and the asymmetrical β-octamolybdate-based hybrid [{Mo2O4(HL2)(H2L)}{MoO2(HL2)}2Mo8O26]·CH3CN·H2O. Quantum chemical calculations were applied to evaluate the impact of the POM hybrid constituents on the hybrid-type stability, showing that it strongly depends on the ligand substituent position and ancillary ligand nature. Hybrids were tested as catalysts for cyclooctene epoxidation using tert-butyl hydroperoxide (TBHP in water or decane) and with or without the addition of acetonitrile (CH3CN) as an organic solvent. The catalytic results provided by the use of TBHP in decane are the best ones and classify all the prepared catalysts as very active, with the conversion of cyclooctene >90%, and high selectivity towards epoxide, >80%. We also examined the influence of the ligand structure, POM's hybrid type, and coordination mode on the Mo-hybrid activity and selectivity.

Rhodium-decorated palladium nanocubes supported on Ni(OH)2 nanosheets/C for enhanced ethanol oxidation

This study investigates the improvement of Palladium (Pd)-based nanocatalysts for ethanol oxidation in alkaline solutions, a process often hindered by the poisoning of the catalyst’s surface. We synthesise Pd nanocubes and Rhodium (Rh)-decorated Pd nanocubes, both supported by a composite of nickel hydroxide nanosheets and carbon (Ni(OH)2/C). The developed Pd nanocatalysts possess a nanocubic morphology with smaller sizes compared to Pd/C, alongside additional nanostructures like nanorods X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses suggest that Rh decoration on Pd nanocubes prevents Pd oxidation, with Rh itself being oxidised. The electrocatalytic performance of the Rh/Pd/Ni(OH)2/C hybrid catalyst displays a notable enhancement, attributed to the combined effects of the exposed Pd (100) crystal surfaces, the addition of oxygenated species through the Ni(OH)2 component, and the deliberate addition of Rh. Comparative assessments reveal that this composite surpasses Pd/C and Pd/C nanocubes, achieving specific activities that are approximately 11.6 and 3.5 times greater, respectively. Electrochemical Impedance Spectroscopy data and chronoamperometric studies confirm superior ethanol oxidation efficiency and improved catalytic stability. These findings highlight the utility of Rh/Pd/Ni(OH)2/C nanocubes in direct ethanol fuel cells, providing promising pathways for enhancing fuel cell technologies.

Noble Metal Plasmon-Molecular Catalyst Hybrids for Renewable Energy Relevant Small Molecule Activation.

Significant endeavors have been dedicated to the advancement of materials for artificial photosynthesis, aimed at efficiently harvesting light and catalyzing reactions such as hydrogen production and CO2 conversion. The application of plasmonic nanomaterials emerges as a promising option for this purpose, owing to their excellent light absorption properties and ability to confine solar energy at the nanoscale. In this regard, coupling plasmonic particles with molecular catalysts offers a pathway to create high-performance hybrid catalysts. In this review, we discuss the plasmonic-molecular complex hybrid catalysts where the plasmonic nanoparticles serve as the light-harvesting unit and promote interfacial charge transfer in tandem with the molecular catalyst which drives chemical transformation. In the initial section, we provide a concise overview of plasmonic nanomaterials and their photophysical properties. We then explore recent breakthroughs, highlighting examples from literature reports involving plasmonic-molecular complex hybrids in various catalytic processes. The utilization of plasmonic materials in conjunction with molecular catalysts represents a relatively unexplored area with substantial potential yet to be realized. This review sets a strong basis and motivation to explore the plasmon-induced hot-electron mediated photelectrochemical small molecule activation reactions. Utilizing in situ spectroscopic investigations and ultrafast transient absorption spectroscopy, it presents a comprehensive template for scalable and sustainable antenna-reactor systems.

Catalytic co-pyrolysis of woody biomass with polypropylene: Effects of Korean loess hybrid catalysts and pyrolysis temperatures

This paper describes an effort to improve the catalytic characteristics of Korean loess (KL) for the co-pyrolysis of biomass and polypropylene, resulting in a unique multifunctional catalyst. Korean loess was physically and chemically transformed into a microporous structure (ZSM) fitting for co-pyrolysis. Using the catalysts manufactured above, analytical co-pyrolysis was carried out using a Py-GC/MS system with pinewood sawdust and polypropylene mixed at a ratio of 1:1 (w/w). To investigate the impacts of the use of catalysts and the pyrolysis temperatures on the distribution of volatile pyrolytic products, the experiments were designed to mix 2- or 8-fold catalyst mass quantities with feedstock and pyrolyze at temperatures of 500 °C, 600 °C, and 700 °C. Compared to pure Korean loess, the catalytic activity of the optimal hybrid catalyst (0.2KL/ZSM) favored decarbonylation over dehydration, making it more effective than mesoporous ZSM. Pyrolytic products generated using the hybrid catalyst (0.2KL/ZSM) had a higher hydrogen concentration (9.8 wt%) than pyrolytic products produced using ZSM catalysts (6.5 wt%). Because of this, the pyrolytic products were expected to be more compatible as a fuel over 0.2KL/ZSM, with an HHV of 27.4 MJ/kg as opposed to 26.5 MJ/kg over ZSM. Zeolite framework catalysts could promote the production of aromatic chemicals (3.0 mg/g for non-catalyst, 34.7 mg/g for KL, and 53.9 mg/g for 0.2KL/ZSM) in the co-pyrolysis of PP with pine, which synergistically enhance oligomerization, cyclization, and aromatization reactions at catalyst acid sites. Concerning aromatic hydrocarbon yields, 0.2KL/ZSM could be expected to perform very similarly to ZSM in producing 74.7 mg/g of MAH+PAH at 600 °C.

Integration Construction of Hybrid Electrocatalysts for Oxygen Reduction.

There is notable progress in the development of efficient oxygen reduction electrocatalysts, which are crucial components of fuel cells. However, these superior activities are limited by imbalanced mass transport and cannot be fully reflected in actual fuel cell applications. Herein, the design concepts and development tracks of platinum (Pt)-nanocarbon hybrid catalysts, aiming to enhance the performance of both cathodic electrocatalysts and fuel cells, are presented. This review commences with an introduction to Pt/C catalysts, highlighting the diverse architectures developed to date, with particular emphasis on heteroatom modification and microstructure construction of functionalized nanocarbons based on integrated design concepts. This discussion encompasses the structural evolution, property enhancement, and catalytic mechanisms of Pt/C-based catalysts, including rational preparation recipes, superior activity, strong stability, robust metal-support interactions, adsorption regulation, synergistic pathways, confinement strategies, ionomer optimization, mass transport permission, multidimensional construction, and reactor upgrading. Furthermore, this review explores the low-barrier or barrier-free mass exchange interfaces and channels achieved through the impressive multidimensional construction of Pt-nanocarbon integrated catalysts, with the goal of optimizing fuel cell efficiency. In conclusion, this review outlines the challenges associated with Pt-nanocarbon integrated catalysts and provides perspectives on the future development trends of fuel cells and beyond.

Fe2O3@ZrO2 catalyst derived from MOF-on-MOF for direct CO2 hydrogenation to light olefins

The utilization of CO2 for the production of light olefins through catalysis with iron-based catalysts presents a viable strategy to address the challenges of carbon neutrality. In this study, we synthesized a novel hybrid catalyst Fe2O3@ZrO2, derived from the pyrolysis of dual metal–organic frameworks (NH2-MIL-88B@UiO-66). Under specific conditions (340 °C, 3.0 MPa, CO2/H2 = 1:3, 10000 mL gcat−1h−1), the Fe2O3@ZrO2 catalyst exhibited a notable space–time yield of light olefins at 12.7 mmol g−1h−1. The characterizations results show an electron transfer from ZrO2 to the Fe2O3 surface was observed at the heterointerface of Fe2O3 and ZrO2. This electron transfer mechanism was identified as advantageous for the formation of the active phase Fe5C2. This research introduces an innovative use of the hybrid Fe2O3@ZrO2 catalyst derived from MOF-on-MOF, holding significant promise in advancing the field of CO2 hydrogenation catalysts.

Dilute RuCo Alloy Synergizing Single Ru and Co Atoms as Efficient and CO‐Resistant Anode Catalyst for Anion Exchange Membrane Fuel Cells

AbstractRuthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and its much higher oxygenophilicity than that of Pt. However, Ru still suffers from insufficient intrinsic activity and CO resistance, which hinders its widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report a hybrid catalyst (RuCo)NC+SAs/N‐CNT consisting of dilute RuCo alloy nanoparticles and atomically single Ru and Co atoms on N‐doped carbon nanotubes The catalyst exhibits a state‐of‐the‐art activity with a high mass activity of 7.35 A mgRu−1. More importantly, when (RuCo)NC+SAs/N‐CNT is used as an anode catalyst for AEMFCs, its peak power density reaches 1.98 W cm−2, which is one of the best AEMFCs properties of noble metal‐based catalysts at present. Moreover, (RuCo)NC+SAs/N‐CNT has superior long‐time stability and CO resistance. The experimental and density functional theory (DFT) results demonstrate that the dilute alloying and monodecentralization of the exotic element Co greatly modulates the electronic structure of the host element Ru, thus optimizing the adsorption of H and OH and promoting the oxidation of CO on the catalyst surface, and then stimulates alkaline HOR activity and CO tolerance of the catalyst.

Dilute RuCo Alloy Synergizing Single Ru and Co Atoms as Efficient and CO-Resistant Anode Catalyst for Anion Exchange Membrane Fuel Cells.

Ruthenium (Ru) is considered a promising candidate catalyst for alkaline hydroxide oxidation reaction (HOR) due to its hydrogen binding energy (HBE) like that of platinum (Pt) and its much higher oxygenophilicity than that of Pt. However, Ru still suffers from insufficient intrinsic activity and CO resistance, which hinders its widespread use in anion exchange membrane fuel cells (AEMFCs). Here, we report a hybrid catalyst (RuCo)NC+SAs/N-CNT consisting of dilute RuCo alloy nanoparticles and atomically single Ru and Co atoms on N-doped carbon nanotubes The catalyst exhibits a state-of-the-art activity with a high mass activity of 7.35 A mgRu -1. More importantly, when (RuCo)NC+SAs/N-CNT is used as an anode catalyst for AEMFCs, its peak power density reaches 1.98 W cm-2, which is one of the best AEMFCs properties of noble metal-based catalysts at present. Moreover, (RuCo)NC+SAs/N-CNT has superior long-time stability and CO resistance. The experimental and density functional theory (DFT) results demonstrate that the dilute alloying and monodecentralization of the exotic element Co greatly modulates the electronic structure of the host element Ru, thus optimizing the adsorption of H and OH and promoting the oxidation of CO on the catalyst surface, and then stimulates alkaline HOR activity and CO tolerance of the catalyst.

A combo Zr–zeolite and Zr(OH)4 mixture composition for one–pot production of γ–valerolactone from furfural

The one–pot cascade transformation of biomass–derived furfural (FUR) to γ–valerolactone (GVL) has attracted great attention but always facing relative low reaction rates. In this work, a combo ZrO2 supported on ZSM–5 nanosheet (ZrO2/NS) and Zr(OH)4 were mixed as a hybrid catalysts system, which was prepared by impregnation and precipitation, respectively. Then the catalytic system was used for conversion of FUR to produce GVL through catalytic transfer hydrogenation in isopropanol. NS zeolite with hierarchical pores promoted the dispersion of ZrO2 and exposed surface assisted the conversion of FUR to isopropyl levulinate (IPL). Moreover, the addition of Zr(OH)4 facilitated the cascade transformation of the intermediate IPL to GVL through the enhanced adsorption of IPL and isopropanol with the cooperation of basic sites. The ZrO2/NS and Zr(OH)4 catalyst system with optimized proportion delivers >90 wt% yield of GVL at 180 °C after 2h reaction, with generation rates of GVL (RGVL) up to 9.2 mmol g−1 h−1.

H2O2-free catalytic dye degradation at dye/night circumstances using CuS@Au heterostructures decorating on MoS2 nanoflowers

Catalytic remediation of industrial organic pollutants is considered effective mitigation of increasing risks from aqueous contaminations composed of hazardous substances. The need for in-situ environmental remediation is highly demanded to deal with organic contaminations from on-site, instant, and full-time treatment without the need to remove the contaminated sources for ex-situ remediation is highly demanded. In this work, by means of combining the strategies of daytime and dark degradation capabilities of organic dyes, the MoS2/Au@CuS hybrid catalysts resembling semiconductor/metal/semiconductor junction features underline the generation of hydroxyl radicals, and force to speed up the oxidative removal of organic dyes during light-on and light-off conditions in both scenarios. Decorations of CuS on hydrothermally synthesized MoS2/Au nanoflowers are prepared with the in-situ chemical reduction process. We reveal that such circumstance exists when programming the environment in the sequence of light-on/light-off conditions, which actively clicks the generation of H2O2 and strategically accelerates the degradation kinetics, offering an additional opportunity for promoting catalytic degradation of hazardous organic dyes with whole-day feasibility.

Enhancement of nitric oxide reduction via CeZrOx/Cu‐SSZ‐39 hybrid catalyst: Improving activity and hydrothermal stability

AbstractThis study aimed to improve the catalytic activity and hydrothermal stability of Cu‐SSZ‐39 zeolite by coupling it with cerium zirconium oxides (CeZrOx), which possesses excellent oxidizing ability, and a hybrid catalyst CeZrOx/Cu‐SSZ‐39 was prepared. It is found that it exhibited enhanced low‐temperature activity, high‐temperature activity, and a wider effective temperature range compared to Cu‐SSZ‐39. Characterization results showed that the CeZrOx/Cu‐SSZ‐39 catalyst had a higher concentration of active Cu2+ ion species and improved redox properties, which could potentially promote the NH3‐SCR reaction. Additionally, the CeZrOx/Cu‐SSZ‐39 catalyst had increased chemisorbed oxygen species on its surface, facilitating the oxidation of NO to NO2 and enhancing the rate of the SCR reaction. Moreover, even after undergoing hydrothermal aging treatment, the CeZrOx/Cu‐SSZ‐39 catalyst exhibited superior catalytic activity and improved hydrothermal stability, surpassing the performance of Cu‐SSZ‐39. It is found the CeZrOx coupling allowed the hybrid catalyst to maintain a better specific surface area and pore structure during hydrothermal aging, resulting in reduced activity loss. Therefore, the addition of CeZrOx enhanced the NH3‐SCR activity of Cu‐SSZ‐39 zeolite, leading to improved catalytic activity and hydrothermal stability. CeZrOx/Cu‐SSZ‐39 catalyst has shown promising aspect for reducing NOx emissions from diesel vehicle exhaust.

NiFeCo alloy nanoparticles composited with phosphorus-doped vacancies-abundant carbon substrates as electrocatalyst for oxygen evolution reaction

Transition metal alloy nanoparticles are cost-effective electrocatalysts for oxygen evolution reactions. Preparing alloy catalysts with flexible controllability, high activity, and long-term stability is a challenge. By adjusting the proportion of metal atoms and engineering vacancies through their composite with a carbon substrate, we can enhance electron transfer and modulate the adsorption capacity of reaction intermediates. Herein, we synthesized a hybrid catalyst using Prussian blue analogs (PBAs) as the precursor, doped with Fe and Ni atoms, and subjected them to a defective engineering and phosphatization process. As an efficient alkaline OER electrocatalyst, the formation of the alloy increases the number of active sites, while the defect-rich phosphorus-doped carbon substrate improves internal electron transfer and mass transfer channels. The synthesized NiFeCoPC-1.5 electrocatalyst exhibits excellent catalytic activity with an overpotential of 211 mV at 10 mA cm−2 and a Tafel slope of 59 mV dec−1, and demonstrates good stability up to 1000 CV cycles. This work will expand the application of alloy nanoparticles in oxygen evolution electrodes.