In this study, a heterogeneous nucleation and growthmodel hasbeen developed to explore the formation mechanism of silver-depositedsilica core-shell particles based on the reaction kinetics.To validate the core-shell model, the time-dependent experimentaldata were quantitatively examined and in situ reduction,nucleation, and growth rates were estimated by optimizing the concentrationprofiles of reactants and deposited silver particles. Using this model,we also attempted to predict the change in the surface area and diameterof core-shell particles. The concentration of the reducingagent, metal precursor, and reaction temperature were found to havea strong influence on the rate constants and morphology of core-shellparticles. Higher rates of nucleation and growth often produced thick,asymmetric patches that covered the entire surface, whereas lowerrates produced sparsely deposited silver particles with a sphericalshape. The result revealed that by simply tuning the process parametersand controlling the relative rates, the morphology of deposited silverparticles and the surface coverage can be controlled while retainingthe spherical shape of the core. The present study aims to offer comprehensivedata pertaining to the nucleation, growth, and coalescence processesof core-shell nanostructures which will aid in the developmentand understanding of the principles that govern the formation of nanoparticle-coatedmaterials.

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