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In Situ Synchrotron X‐ray Characterization Shining Light on the Nucleation and Growth Kinetics of Colloidal Nanoparticles

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Angewandte Chemie International Edition
Authors:
Siyu Wu at Temple University
Siyu Wu
Mingrui Li
Mingrui Li
Mingrui Li
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Yugang Sun at Temple University
Yugang Sun
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Abstract and Figures

Rational synthesis of colloidal nanoparticles with desirable properties relies on precise control over the nucleation and growth kinetics, which is still not well understood. The recent development of in situ high energy synchrotron X‐ray techniques offers an excellent opportunity to quantitatively monitor the growth trajectories of colloidal nanoparticles in real time under real reaction conditions. The time‐resolved, quantitative data of the growing colloidal nanoparticles are unique to reveal the mechanism of nanoparticle formation and determine the corresponding intrinsic kinetic parameters. This review discusses the kinetics of major steps of forming colloidal nanoparticles and the capability of in situ synchrotron X‐ray techniques in studying the corresponding kinetics.
Schematic illustration of time‐dependent evolution of concentrations of precursor reactant (red), nanoparticle precursor (green), and size of nanoparticles (blue) involved in a typical synthesis of colloidal nanoparticles. The major steps are (I) nucleation, (II) early growth, and (III) late growth stages. The background sketches the evolution of NPs from reactant. The lower part highlights the appropriate in situ X‐ray techniques for different evolution periods.
Schematic illustration of time‐dependent evolution of concentrations of precursor reactant (red), nanoparticle precursor (green), and size of nanoparticles (blue) involved in a typical synthesis of colloidal nanoparticles. The major steps are (I) nucleation, (II) early growth, and (III) late growth stages. The background sketches the evolution of NPs from reactant. The lower part highlights the appropriate in situ X‐ray techniques for different evolution periods.
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a) In situ SAXS patterns of growing Pd CNPs recorded at various times. The dotted plots and solid plots are experimental data and the corresponding fitting results, respectively. The extracted time‐dependent b) concentration and c) size (symbols) and size distribution (error bars) of the Pd CNPs determined from analysis of the in situ SAXS patterns. d) Time‐dependent temperature of the synthesis solution. Adapted from ref. 26 with permission. Copyright 2018, American Chemical Society.
a) In situ SAXS patterns of growing Pd CNPs recorded at various times. The dotted plots and solid plots are experimental data and the corresponding fitting results, respectively. The extracted time‐dependent b) concentration and c) size (symbols) and size distribution (error bars) of the Pd CNPs determined from analysis of the in situ SAXS patterns. d) Time‐dependent temperature of the synthesis solution. Adapted from ref. 26 with permission. Copyright 2018, American Chemical Society.
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a) Time‐resolved in situ SAXS patterns of CNPs in a synthesis of CoPt3/Au dumbbell‐like hybrid particles (inset, top right) by using spherical CoPt3 CNPs as seeds (inset, bottom left). Time‐dependent b) fraction of dumbbell‐like NPs (fdb=ndbnseed+ndb ) and c) average size of dumbbell‐like NPs (red), CoPt3 seed NPs (green), and Au domains (purple circle) obtained from analysis of SAXS patterns in (a). Adapted from ref. 39 with permission. Copyright 2014, Nature Publishing Group.
a) Time‐resolved in situ SAXS patterns of CNPs in a synthesis of CoPt3/Au dumbbell‐like hybrid particles (inset, top right) by using spherical CoPt3 CNPs as seeds (inset, bottom left). Time‐dependent b) fraction of dumbbell‐like NPs (fdb=ndbnseed+ndb ) and c) average size of dumbbell‐like NPs (red), CoPt3 seed NPs (green), and Au domains (purple circle) obtained from analysis of SAXS patterns in (a). Adapted from ref. 39 with permission. Copyright 2014, Nature Publishing Group.
… 
Time‐resolved a) in situ WAXS patterns and b) the corresponding aspect ratio defined by the lateral dimensions along c to a of the growing ZnO CNPs. Adapted from ref. 46 with permission. Copyright 2014, American Chemical Society.
Time‐resolved a) in situ WAXS patterns and b) the corresponding aspect ratio defined by the lateral dimensions along c to a of the growing ZnO CNPs. Adapted from ref. 46 with permission. Copyright 2014, American Chemical Society.
… 
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German Edition:DOI:10.1002/ange.201900690
Colloidal Nanoparticles International Edition:DOI:10.1002/anie.201900690
In Situ Synchrotron X-ray Characterization Shining
Light on the Nucleation and Growth Kinetics of
Colloidal Nanoparticles
Siyu Wu,Mingrui Li, and Yugang Sun*
Angewandte
Chemie
Keywords:
colloidal nanoparticles ·crystal growth ·
in situ characterization ·
synchrotron X-ray scattering ·
time-resolved spectrosco-
py
A
ngewandte
Chemie
Minireviews
8987Angew.Chem. Int.Ed. 2019,58,8987 –8995 T2019 Wiley-VCH Verlag GmbH &Co. KGaA, Weinheim
... atom scale, particle scale, etc.), (ii) to investigate pre-nucleation clusters and other metastable early products, and (iii) to study particle properties such as size, morphology, and aggregation, as well as the crystalline order. 5 This approach gives the best results in combination with synchrotron light, as the high radiation brilliance allows to acquire data with high temporal resolution as well as lowintensity signals, and thus is perfect for investigating the early stages of NPs formation or subtle changes that might occur during crystallization. 5 The use of Small Angle X-ray Scattering (SAXS) allows to evaluate particle size, morphology, and their distribution in the population. ...
... 5 This approach gives the best results in combination with synchrotron light, as the high radiation brilliance allows to acquire data with high temporal resolution as well as lowintensity signals, and thus is perfect for investigating the early stages of NPs formation or subtle changes that might occur during crystallization. 5 The use of Small Angle X-ray Scattering (SAXS) allows to evaluate particle size, morphology, and their distribution in the population. Therefore it enables to follow the formation of nuclei, their growth into particles, and particle maturation, especially in the case of nanomaterials. ...
... Therefore, the combination of Small and Wide X-ray Scattering (SAXS/WAXS) allows to fully track the growth kinetics of crystalline NPs such as CaP NPs, thus obtaining simultaneous structural and chemical insights ranging from atomic to nanometric scale with high time resolution. 5,7,8 Synchrotron light combined SAXS/WAXS was previously used to study biogenic and synthetic CaP, but only as ex situ measurements. 2,9 Recently, we have investigated the formation of CaP NPs and their crystallization into hydroxyapatite (HA, Ca 10 (PO 4 ) 6 (OH) 2 ) nanocrystals in presence of three structurally similar calciumbinding carboxylate molecules in terms of crystal growth, chemical composition, and morphology. ...
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