Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

Chemical Reviews, Год журнала: 2023, Номер 123(8), С. 4855 - 4933

Опубликована: Март 27, 2023

Heterogeneous bimetallic catalysts have broad applications in industrial processes, but achieving a fundamental understanding on the nature of active sites at atomic and molecular level is very challenging due to structural complexity catalysts. Comparing features catalytic performances different entities will favor formation unified structure-reactivity relationships heterogeneous thereby facilitate upgrading current In this review, we discuss geometric electronic structures three representative types (bimetallic binuclear sites, nanoclusters, nanoparticles) then summarize synthesis methodologies characterization techniques for entities, with emphasis recent progress made past decade. The supported nanoparticles series important reactions are discussed. Finally, future research directions catalysis based and, more generally, prospective developments both practical applications.

Язык: Английский

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Internal quantum efficiency higher than 100% achieved by combining doping and quantum effects for photocatalytic overall water splitting

Nature Energy, Год журнала: 2023, Номер 8(5), С. 504 - 514

Опубликована: Апрель 10, 2023

Язык: Английский

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Elucidating the Near-Infrared Photoluminescence Mechanism of Homometal and Doped M₂₅(SR)₁₈ Nanoclusters

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(36), С. 19969 - 19981

Опубликована: Авг. 29, 2023

More than a decade of research on the photoluminescence (PL) classic Au25(SR)18 and its doped nanoclusters (NCs) still leaves many fundamental questions unanswered due to complex electron dynamics. Here, we revisit homogold Au25 (ligands omitted hereafter) NCs, as well Ag25 ones, for comparative study disentangle influencing factors elucidate PL mechanism. We find that strong electron-vibration coupling in leads weak near-infrared region (∼1000 nm, quantum yield QY = 1% solution at room temperature). Heteroatom doping with single Cd or Hg atom strengthens exciton staple vibrations but reduces core breathing quadrupolar modes. The QYs three MAu24 NCs (M Hg, Au, Cd) follow linear relation their lifetimes, suggesting mechanism suppressed nonradiative decay enhancement. In contrast, weaker higher (QY 3.5%), Au further 5× enhancement radiative rate suppression (i.e., twice lifetime Ag25) AuAg24 (hence, 35%), more atoms results gold distribution motifs thus triggering hence, counteracting effect giving rise only 5% AuxAg25-x (x 3-10). obtained insights will provide guidance design metal high lighting, sensing, optoelectronic applications.

Язык: Английский

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Visible to NIR‐II Photoluminescence of Atomically Precise Gold Nanoclusters

Advanced Materials, Год журнала: 2023, Номер 36(8)

Опубликована: Ноя. 3, 2023

Abstract Atomically precise gold nanoclusters (NCs) have emerged as a new class of precision materials and attracted wide interest in recent years. One the unique properties such pertains to their photoluminescence (PL), for it can widely span visible near‐infrared–I –II wavelengths (NIR‐I/II), even beyond 1700 nm by manipulating size, structure, composition. The current research efforts focus on structure–PL correlation development strategies raising PL quantum yields, which is nontrivial when moving from near‐infrared wavelengths, especially NIR–II regions. This review summarizes progress field, including i) types observed NCs fluorescence, phosphorescence, thermally activated delayed well dual emission; ii) some effective that are devised improve yield (QY) NCs, heterometal doping, surface rigidification, core phonon engineering, with double‐digit QYs NIR horizons; iii) applications luminescent bioimaging, photosensitization, optoelectronics. Finally, remaining challenges opportunities future highlighted.

Язык: Английский

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Atom‐Precise Heteroatom Core‐Tailoring of Nanoclusters for Enhanced Solar Hydrogen Generation

Advanced Materials, Год журнала: 2023, Номер 35(18)

Опубликована: Фев. 11, 2023

While core-shell nanomaterials are highly desirable for realizing enhanced optical and catalytic properties, their synthesis with atomic-level control is challenging. Here, the crystal structure of [Au12 Ag32 (SePh)30 ]4- , first example selenolated Au-Ag nanoclusters, comprising a gold icosahedron core trapped in silver dodecahedron, which protected by an Ag12 shell, presented. The strongly modifies overall electronic induces synergistic effects, resulting high enhancements stability near-infrared-II photoluminescence. Au12 its homometal analog Ag44 show strong interactions oxygen vacancies TiO2 facilitating interfacial charge transfer photocatalysis. Indeed, /TiO2 exhibits remarkable solar H2 production (6810 µmol g-1 h-1 ), ≈6.2 ≈37.8 times higher than that respectively. Good recyclability minimal activity loss additional features . experimental computational results reveal acts as efficient cocatalyst possessing favorable aligns well bands separation photoinduced carriers due to relatively negatively charged core. These atomistic insights will motivate uncovering structure-catalytic relationships other nanoclusters.

Язык: Английский

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Tailoring Carbon Tails of Ligands on Au₅₂(SR)₃₂ Nanoclusters Enhances the Near-Infrared Photoluminescence Quantum Yield from 3.8 to 18.3%

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(48), С. 26328 - 26338

Опубликована: Ноя. 20, 2023

One of the important factors that determine photoluminescence (PL) properties gold nanoclusters pertain to surface. In this study, four Au52(SR)32 feature a series aromatic thiolate ligands (-SR) with different bulkiness at para-position are synthesized and investigated. The near-infrared (NIR) (peaks 900-940 nm) quantum yield (QY) is largely enhanced decrease in ligand's para-bulkiness. Specifically, capped least bulky p-methylbenzenethiolate (p-MBT) exhibits highest PLQY (18.3% room temperature non-degassed dichloromethane), while Au52 bulkiest tert-butylbenzenethiolate (TBBT) only gives 3.8%. large enhancement QY fewer methyl groups on implies nonradiative decay via multiphonon process mediated by C-H bonds. Furthermore, single-crystal X-ray diffraction (SCXRD) comparison Au52(p-MBT)32 Au52(TBBT)32 reveals lead stronger interligand π···π stacking core, thus restricting ligand vibrations rotations. emission nature identified be phosphorescence thermally activated delayed fluorescence (TADF) based PL lifetime, 3O2 quenching, temperature-dependent absorption studies. 1O2 generation efficiencies for NCs follow same trend as observed performance. Overall, highly NIR-luminescent nanocluster revealed mechanisms expected find future applications.

Язык: Английский

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Photoluminescent Characterization of Metal Nanoclusters: Basic Parameters, Methods, and Applications

Advanced Materials, Год журнала: 2024, Номер 36(25)

Опубликована: Март 24, 2024

Abstract Metal nanoclusters (MNCs) can be synthesized with atomically precise structures and molecule formulae due to the rapid development of nanocluster science in recent decades. The ultrasmall size range (normally < 2 nm) endows MNCs plenty molecular‐like properties, among which photoluminescent properties have aroused extensive attention. Tracing research processes luminescent nanoclusters, various analysis characterization methods play a significant role elucidating mechanism analyzing properties. In this review, it is aimed systematically summarize normally used characterizations including basic parameters methods, such as excitation/emission wavelength, quantum yield, lifetime. For each key parameter, first its definition meaning introduced then relevant measuring principles revelation from collected data are discussed. Then, discussed details how explore construct NC‐based applications based on measured data. By means these strategies, designs explained quantitatively qualitatively. Hence, review expected provide clear guidance for researchers characterize better understand results.

Язык: Английский

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Near-Infrared Dual Emission from the Au₄₂(SR)₃₂ Nanocluster and Tailoring of Intersystem Crossing

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(42), С. 19243 - 19247

Опубликована: Окт. 14, 2022

This work presents the synthesis and intriguing photoluminescence of Au42(PET)32 (PET = 2-phenylethanethiolate) nanocluster (NC). The NC exhibits dual emission at 875 1040 nm, which are revealed to be fluorescence phosphorescence, respectively. quantum yield (QY) in dichloromethane is 11.9% room temperature air, quite rare for thiolate-protected Au NCs. When NCs embedded polystyrene films (solid state), was dramatically suppressed while phosphorescence significantly enhanced. divergent behavior explained by dipolar interaction-induced enhancement intersystem crossing from singlet triplet excited state.

Язык: Английский

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Isostructural Nanocluster Manipulation Reveals Pivotal Role of One Surface Atom in Click Chemistry

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(37)

Опубликована: Июль 20, 2023

Elucidating single-atom effects on the fundamental properties of nanoparticles is challenging because modifications are typically accompanied by appreciable changes to overall particle's structure. Herein, we report synthesis a [Cu58 H20 PET36 (PPh3 )4 ]2+ (Cu58 ; PET: phenylethanethiolate; PPh3 : triphenylphosphine) nanocluster-an atomically precise nanoparticle-that can be transformed into surface-defective analog [Cu57 ]+ (Cu57 ). Both nanoclusters virtually identical, with five concentric metal shells, save for one missing surface copper atom in Cu57 . Remarkably, loss this single drastically alters reactivity nanocluster. In contrast Cu58 , shows promising activity click chemistry, particularly photoinduced [3+2] azide-alkyne cycloaddition (AAC), which attributed active catalytic site after removal atom. Our study not only presents unique system uncovering effect single-surface modification nanoparticle but also showcases as powerful means designing catalysts.

Язык: Английский

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Excited State Engineering in Ag₂₉ Nanocluster through Peripheral Modification with Silver(I) Complexes for Bright Near-Infrared Photoluminescence

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(20), С. 11236 - 11244

Опубликована: Апрель 26, 2023

The optical property of an ionic metal nanocluster (NC) is affected by the interaction with counter ions. Here, we report that modification trianionic [Ag29(BDT)12(TPP)4]3- NC (BDT: 1.3-benzenedithiol; TPP: triphenylphosphine) silver(I) complexes led to intense photoluminescence (PL) in near-infrared (NIR) region. binding peripheral region Ag29 confirmed single-crystal X-ray diffraction (SCXRD) measurement, which further supported electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy. change excited-state dynamics discussed based on results a transient absorption study as well temperature-dependent PL spectra lifetime measurements. NCs cationic considered give rise triplet excited state responsible for NIR PL. These findings also afford important insights into origin mechanism possible light-driven motion Ag29-based NCs.

Язык: Английский

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