Atomically Precise Clusters of Noble Metals: Emerging Link between Atoms and Nanoparticles

Chemical Reviews, Год журнала: 2017, Номер 117(12), С. 8208 - 8271

Опубликована: Июнь 6, 2017

Atomically precise pieces of matter nanometer dimensions composed noble metals are new categories materials with many unusual properties. Over 100 molecules this kind formulas such as Au25(SR)18, Au38(SR)24, and Au102(SR)44 well Ag25(SR)18, Ag29(S2R)12, Ag44(SR)30 (often a few counterions to compensate charges) known now. They can be made reproducibly robust synthetic protocols, resulting in colored solutions, yielding powders or diffractable crystals. distinctly different from nanoparticles their spectroscopic properties optical absorption emission, showing well-defined features, just like molecules. show isotopically resolved molecular ion peaks mass spectra provide diverse information when examined through multiple instrumental methods. Most important these is luminescence, often the visible–near-infrared window, useful biological applications. Luminescence visible region, especially by clusters protected proteins, large Stokes shift, has been used for various sensing applications, down tens molecules/ions, air water. Catalytic clusters, oxidation organic substrates, have examined. Materials science systems presents numerous possibilities fast evolving. Computational insights given reasons stability The nature unequivocally manifested recent studies intercluster reactions forming clusters. These manifest core, ligand shell, that integrated system. better described aspicules, where aspis means shield cules refers molecules, implying they "shielded molecules". In order understand properties, nomenclature introduced which it possible draw structures positional labels on paper, some training. Research area captured here, based publications available up December 2016.

Язык: Английский

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General synthesis and definitive structural identification of MN4C4 single-atom catalysts with tunable electrocatalytic activities

Nature Catalysis, Год журнала: 2017, Номер 1(1), С. 63 - 72

Опубликована: Дек. 22, 2017

Язык: Английский

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Single‐Atom Electrocatalysts

Angewandte Chemie International Edition, Год журнала: 2017, Номер 56(45), С. 13944 - 13960

Опубликована: Май 24, 2017

Abstract Recent years have witnessed a dramatic increase in the production of sustainable and renewable energy. However, electrochemical performances various systems are limited, there is an intensive search for highly efficient electrocatalysts by more rational control over size, shape, composition, structure. Of particular interest studies on single‐atom catalysts (SACs), which sparked new interests electrocatalysis because their high catalytic activity, stability, selectivity, 100 % atom utilization. In this Review, we introduce innovative syntheses characterization techniques SACs, with focus applications oxygen reduction/evolution reaction, hydrogen evolution hydrocarbon conversion reactions fuel cells (electrooxidation methanol, ethanol, formic acid). The electrocatalytic performance further considered at atomic level underlying mechanisms discussed. ultimate goal tailoring single atoms applications.

Язык: Английский

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Catalysis by Supported Single Metal Atoms

ACS Catalysis, Год журнала: 2016, Номер 7(1), С. 34 - 59

Опубликована: Окт. 18, 2016

The recent explosive growth in research on catalysis by supported single metal atoms proves the scientific interest this new frontier of heterogeneous catalysis. A single-atom catalyst (SAC) contains only isolated individual dispersed on, and/or coordinated with, surface an appropriate support. SACs not maximize atom efficiency expensive metals but also provide alternative strategy to tune activity and selectivity a catalytic reaction. When are strongly anchored onto high-surface-area supports, offer great potential significantly transform field catalysis, which has been critical enabling many important technologies. In Perspective, I discuss most advances preparing, characterizing, catalytically testing with focus correlating structural perspective observed performances. grand challenge successfully developing practical is find approaches anchor keep them stable functional during desired reactions. will highlight overcome barrier develop for variety transformations molecules.

Язык: Английский

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Atomically Precise Noble Metal Nanoclusters as Efficient Catalysts: A Bridge between Structure and Properties

Chemical Reviews, Год журнала: 2019, Номер 120(2), С. 526 - 622

Опубликована: Март 22, 2019

Improving the knowledge of relationship between structure and properties is fundamental in catalysis. Recently, researchers have developed a variety well-controlled methods to synthesize atomically precise metal nanoclusters (NCs). NCs shown high catalytic activity unique selectivity many reactions, which are related their ultrasmall size, abundant unsaturated active sites, electronic different from that traditional nanoparticles (NPs). More importantly, because definite monodispersity, they used as model catalysts reveal correlation catalyst performance at atomic scale. Therefore, this review aims summarize recent progress on catalysis provide potential theoretical guidance for rational design high-performance catalysts. First brief summary synthetic strategies characterization provided. Then primary focus review-the role catalysis-is illustrated experimental perspectives, particularly electrocatalysis, photocatalysis, photoelectric conversion, organic reactions. Finally, main challenges opportunities examined deep understanding key steps with goal expanding application range NCs.

Язык: Английский

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Single Atom (Pd/Pt) Supported on Graphitic Carbon Nitride as an Efficient Photocatalyst for Visible-Light Reduction of Carbon Dioxide

Journal of the American Chemical Society, Год журнала: 2016, Номер 138(19), С. 6292 - 6297

Опубликована: Апрель 26, 2016

Reducing carbon dioxide to hydrocarbon fuel with solar energy is significant for high-density storage and balance. In this work, single atoms of palladium platinum supported on graphitic nitride (g-C3N4), i.e., Pd/g-C3N4 Pt/g-C3N4, respectively, acting as photocatalysts CO2 reduction were investigated by density functional theory calculations the first time. During reduction, individual metal function active sites, while g-C3N4 provides source hydrogen (H*) from evolution reaction. The complete, as-designed exhibit excellent activity in reduction. HCOOH preferred product catalyst a rate-determining barrier 0.66 eV, Pt/g-C3N4 prefers reduce CH4 1.16 eV. addition, deposition atom catalysts significantly enhances visible-light absorption, rendering them ideal CO2. Our findings open new avenue renewable supply.

Язык: Английский

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Well-Defined Materials for Heterogeneous Catalysis: From Nanoparticles to Isolated Single-Atom Sites

Chemical Reviews, Год журнала: 2019, Номер 120(2), С. 623 - 682

Опубликована: Дек. 23, 2019

The use of well-defined materials in heterogeneous catalysis will open up numerous new opportunities for the development advanced catalysts to address global challenges energy and environment. This review surveys roles nanoparticles isolated single atom sites catalytic reactions. In second section, effects size, shape, metal-support interactions are discussed nanostructured catalysts. Case studies summarized illustrate dynamics structure evolution under certain reaction conditions. third we syntheses applications atomic anchored on different types supports. final part, conclude by highlighting catalyst gaining a fundamental understanding their active sites.

Язык: Английский

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Low-Temperature CO₂ Methanation over CeO₂-Supported Ru Single Atoms, Nanoclusters, and Nanoparticles Competitively Tuned by Strong Metal–Support Interactions and H-Spillover Effect

ACS Catalysis, Год журнала: 2018, Номер 8(7), С. 6203 - 6215

Опубликована: Май 24, 2018

CO2 hydrogenation for the acquisition of value-added chemicals is an economical means to deal with CO2-relevant environmental problems, among which reduction CH4 excellent model reaction investigating initial steps hydrogenation. For supported catalysts commonly used in such reactions, tailoring interfacial effect between metal centers and supporting materials so as obtain superior low-temperature methanation performance a significant but challenging subject. In this work, we altered size regimes Ru deposits Ru/CeO2 assemblies uncovered competitive relationship strong metal–support interactions (SMSI) H-spillover determining activities by some ex situ spectroscopic techniques coupled density functional theory (DFT) calculations. CeO2 nanowire single atoms, nanoclusters (ca. 1.2 nm size), large nanoparticles 4.0 show most outstanding activity 98–100% selectivity, turnover frequency (TOF) 7.41 × 10–3 s–1 at 190 °C. The negative order decreases their absolute values from atoms turns positive nanoparticles, while H2 follows reverse tendency. DRIFTS measurements demonstrate that dominant pathway CO route, carbonyls are critical intermediates active sites those Ce3+–OH near interfaces charge dissociation carbonyl hydrogenation, respectively. Meanwhile, strongest SMSI respectively encountered activation dehydration support surfaces suppressed correspondingly. two factors reach balance CeO2-supported nanoclusters, therefore maximized. A mechanistic understanding tuning would shed light on ingenious design utilize appropriate degree avoid possible suppressions take place extreme cases.

Язык: Английский

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Synergetic interaction between neighbouring platinum monomers in CO2 hydrogenation

Nature Nanotechnology, Год журнала: 2018, Номер 13(5), С. 411 - 417

Опубликована: Март 19, 2018

Язык: Английский

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Encapsulated Metal Nanoparticles for Catalysis

Chemical Reviews, Год журнала: 2020, Номер 121(2), С. 834 - 881

Опубликована: Июнь 25, 2020

Metal nanoparticles have drawn great attention in heterogeneous catalysis. One challenge is that they are easily deactivated by migration-coalescence during the catalysis process because of their high surface energy. With rapid development nanoscience, encapsulating metal nanoshells or nanopores becomes one most promising strategies to overcome stability issue nanoparticles. Besides, activity and selectivity could be simultaneously enhanced taking advantage synergy between materials as well molecular sieving property materials. In this review, we provide a comprehensive summary recent progress synthesis catalytic properties encapsulated This review begins with an introduction synthetic for different architectures developed date, including encapsulation inorganic oxides carbon, porous (zeolites, metal-organic frameworks, covalent organic frameworks), capsules (dendrimers cages). The advantages then discussed, such recyclability, improved selectivity, strong metal-support interactions, capability enabling tandem catalysis, followed some representative applications thermo-, photo-, electrocatalysis. At end discuss remaining challenges associated our perspectives on future field.

Язык: Английский

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