Metal and Metal Oxide Supported on Ordered Mesoporous Carbon as Heterogeneous Catalysts

ACS Catalysis, Год журнала: 2023, Номер 13(7), С. 4060 - 4090

Опубликована: Март 9, 2023

The evolution of model catalyst systems has experienced single-crystal surfaces different transition metals and crystal faces, two-dimensional with nanoparticles (NPs) deposited on a flat support surface, three-dimensional NPs loaded into the high-surface-area supports such as ordered mesoporous materials. latter two mimic nanoparticle properties in industrial catalysts. Ordered carbon (OMC) materials play unparalleled roles catalysis, energy storage, adsorption, chromatographic separation, etc. because their distinctive structure which allows Knudsen diffusion inside mesopores, dispersion oxides, embedment pore walls. In this review, synthesis routes OMC-supported metal or oxide catalysts, including hard-templating soft-templating methods, are briefly introduced. Mass transfer reactant chemisorption metals, discrimination active species, catalytic reaction mechanism catalysts systemically summarized, highlight advantages catalysis occurring mesopores. Understanding these molecular-dominated factors provides insight controlling highly selective reactions and, therefore, design long life.

Язык: Английский

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Advancements in Noble Metal-Decorated Porous Carbon Nanoarchitectures: Key Catalysts for Direct Liquid Fuel Cells

ACS Nano, Год журнала: 2024, Номер 18(15), С. 10341 - 10373

Опубликована: Апрель 4, 2024

Noble-metal nanocrystals have emerged as essential electrode materials for catalytic oxidation of organic small molecule fuels in direct liquid fuel cells (DLFCs). However, large-scale commercialization DLFCs, adopting cost-effective techniques and optimizing their structures using advanced matrices are crucial. Notably, noble metal-decorated porous carbon nanoarchitectures exhibit exceptional electrocatalytic performances owing to three-dimensional cross-linked networks, large accessible surface areas, homogeneous dispersion (of metals), reliable structural stability, outstanding electrical conductivity. Consequently, they can be utilized develop next-generation anode catalysts DLFCs. Considering the recent expeditious advancements this field, comprehensive review provides an overview current progress nanoarchitectures. This paper meticulously outlines associated synthetic strategies, precise microstructure regulation techniques, application electrooxidation molecules. Furthermore, highlights research challenges future opportunities prospective offering valuable insights both researchers industry experts.

Язык: Английский

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Enhancing Photocatalytic‐Transfer Semi‐Hydrogenation of Alkynes Over Pd/C₃N₄ Through Dual Regulation of Nitrogen Defects and the Mott–Schottky Effect

Advanced Materials, Год журнала: 2023, Номер 35(41)

Опубликована: Июль 5, 2023

The selective hydrogenation of alkynes is an important reaction; however, the catalytic activity and selectivity in this reaction are generally conflicting. In study, ultrafine Pd nanoparticles (NPs) loaded on a graphite-like C3 N4 structure with nitrogen defects (Pd/DCN) synthesized. resulting Pd/DCN exhibits excellent photocatalytic performance transfer ammonia borane. rate superior to those Pd/BCN (bulk without defects) under visible-light irradiation. characterization results density functional theory calculations show that Mott-Schottky effect can change electronic NPs, thus enhances toward phenylacetylene. After 1 h, reaches 95%, surpassing (83%). Meanwhile, supports improve response accelerate separation photogenerated charges enhance Pd/DCN. Therefore, higher efficiency visible light, turnover frequency (TOF) 2002 min-1 . This TOF five times dark conditions 1.5 Pd/BCN. study provides new insights into rational design high-performance catalysts.

Язык: Английский

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Strengthened H₂O adsorption and photogenerated carrier separation: surface C-coupled hydroxylation of g-C₃N₄ photocatalysts for efficient H₂ production

Journal of Materials Chemistry A, Год журнала: 2024, Номер 12(8), С. 4854 - 4865

Опубликована: Янв. 1, 2024

C-coupled hydroxylated g-C 3 N 4 was fabricated via a facile method for efficient photocatalytic hydrogen evolution.

Язык: Английский

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Highly efficient CO₂ electrochemical reduction on dual metal (Co–Ni)–nitrogen sites

Journal of Materials Chemistry A, Год журнала: 2024, Номер 12(8), С. 4601 - 4609

Опубликована: Янв. 1, 2024

A new Co–Ni–N–C electrocatalyst for CO 2 reduction, featuring diatomic metal-nitrogen sites on N-doped carbon, has been developed. It shows high yield and faradaic efficiency, promising various electrochemical reactions.

Язык: Английский

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One‐Step Synthesis of Copper Single‐Atom Nanozymes for Electrochemical Sensing Applications

Small Science, Год журнала: 2024, Номер 4(4)

Опубликована: Фев. 10, 2024

Single‐atom nanozymes (SANs) combine the natural enzymatic properties of nanomaterials with atomic distribution metallic sites over a suitable support. Unfortunately, their synthesis is complicated by some key factors, like poor loading, aggregation, time consumption, and low yield. Herein, copper SANs, surface metal loading (1.47% ± 0.16%) are synthesized, through green, facile, minimal solution processing, single‐step procedure, using CO 2 laser to promote anchoring precursor while simultaneously generating laser‐scribed graphene (LSG) support out polyimide sheet. The presence Cu on LSG verified high‐angle‐annular dark‐field–scanning transmission electron microscopy X‐ray photoelectron spectroscopy. To explore advantages incurred incorporation SANs LSG, material used as working electrode an electrochemical sensor for amperometric detection H O , achieving limit 2.40 μM. findings suggest that CuSANs can confer enhanced sensitivity which essential oxidative stress assessment, reaching values up 130.0 μA mM −1 cm −2 .

Язык: Английский

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Heteroatoms‐Stabilized Single Palladium Atoms on Amorphous Zeolites: Breaking the Tradeoff between Catalytic Activity and Selectivity for Alkyne Semihydrogenation

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(44)

Опубликована: Июль 29, 2024

As a fundamental industrial catalytic process, the semihydrogenation of alkynes presents challenge in striking balance between activity and selectivity due to issue over-hydrogenation. Herein, we develop an efficient system based on single-atom Pd catalysts supported boron-containing amorphous zeolites (Pd/AZ-B), achieving tradeoff breaking for selective hydrogenation alkynes. Advanced characterizations theoretical density functional theory calculations confirm that incorporated B atoms Pd/AZ-B can not only alter geometric electronic properties by controlling electron migration from but also mitigate interaction alkene catalyst supports. This boosts exceptional efficacy phenylacetylene styrene under mild conditions (298 K, 2 bar H

Язык: Английский

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Encapsulation of Pd Single-Atom Sites in Zeolite for Highly Efficient Semihydrogenation of Alkynes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(34), С. 24033 - 24041

Опубликована: Авг. 15, 2024

Palladium (Pd)-based single-atom catalysts (SACs) have shown outstanding selectivity for semihydrogenation of alkynes, but most Pd single sites coordinated with highly electronegative atoms (such as N, O, and S) supports will result in a decrease the electron density sites, thereby weakening adsorption reactants reducing catalytic performance. Constructing rich outer-shell environment by changing coordination structure offers novel opportunity to enhance efficiency excellent alkene selectivity. Therefore, this work, we first propose situ preparation isolated encapsulated within Al/Si-rich ZSM-5 using one-pot seed-assisted growth method.

Язык: Английский

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Precisely Designed Nitrogen-Doped Mesoporous Carbon Sphere-Confined Electron-Deficient Pd Nanoclusters with Enhanced Catalytic Hydrogenation Performance

ACS Catalysis, Год журнала: 2024, Номер 14(11), С. 8619 - 8630

Опубликована: Май 20, 2024

The controlled fabrication of metal nanocluster-based catalysts with high catalytic performance and stability is currently a research hotspot, while it still challenge. Herein, nitrogen-doped mesoporous carbon spheres (CS-N) regular open structure were precisely designed prepared. Pd nanoclusters an average size 1.44 nm highly dispersed stably confined in the radial CS-N, forming Pd/CS-N catalysts. obtained showed hydrogenation phenol to cyclohexanone benzoic acid cyclohexanecarboxylic (yield almost 99%) under mild reaction conditions, outperforming most reported nanoparticle-based Theoretical calculation illustrates that nanocluster exists as electron-deficient state on Pd/CS-N, thus can efficiently facilitate reactant preadsorption activation, also reduce Gibbs free energy rate-determining step reactions. Moreover, catalyst exhibited good reusability stability. Thus, this work will promote precise construction stable catalysts, enabling efficient

Язык: Английский

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Incorporation of Pd Single‐atom Sites in Perovskite with an Excellent Selectivity toward Photocatalytic Semihydrogenation of Alkynes

Angewandte Chemie International Edition, Год журнала: 2024, Номер unknown

Опубликована: Июль 27, 2024

Abstract Semihydrogenation is a crucial industrial process. Noble metals such as Pd have been extensively studied in semihydrogenation reactions, owing to their unique catalytic activity toward hydrogen activation. However, the overhydrogenation of alkenes alkanes often happens due rather strong adsorption on active phases. Herein, we demonstrate that incorporation phases single‐atom sites perovskite lattices SrTiO 3 can greatly alternate electronic structure and coordination environment facilitate desorption than further hydrogenation. Furthermore, incorporated be well stabilized without sintering by host–guest interaction with during activation H species hydrogenation reactions. As result, (Pd‐SrTiO ) exhibits an excellent time‐independent selectivity (>99.9 %) robust durability for photocatalytic phenylacetylene styrene. This strategy based will broad implications development high‐performance photocatalysts selective

Язык: Английский

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