Abstract 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.
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Simulated annealing fitting: a global optimization method for quantitatively analyzing growth kinetics of colloidal Ag nanoparticles
The involvement of heterogeneous solid/liquid reactions in growing colloidal nanoparticles makes it challenging to quantitatively understand the fundamental steps that determine nanoparticles' growth kinetics. A global optimization protocol relying on simulated annealing fitting and the LSW growth model is developed to analyze the evolution data of colloidal silver nanoparticles synthesized from a microwave-assisted polyol reduction reaction. Fitting all data points of the entire growth process determines with high fidelity the diffusion coefficient of precursor species and the heterogeneous reduction reaction rate parameters on growing silver nanoparticles, which represent the principal functions to determine the growth kinetics of colloidal nanoparticles. The availability of quantitative results is critical to understanding the fundamentals of heterogeneous solid/liquid reactions, such as identifying reactive species and reaction activation energy barriers.
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- Award ID(s):
- 1946912
- PAR ID:
- 10279891
- Date Published:
- Journal Name:
- Nanoscale Horizons
- Volume:
- 6
- Issue:
- 7
- ISSN:
- 2055-6756
- Page Range / eLocation ID:
- 568 to 573
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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