Article

Growth Kinetics of Asymmetric Bi(2)S(3) Nanocrystals: Size Distribution Focusing in Nanorods

JOURNAL OF PHYSICAL CHEMISTRY C 115:7947-7955. pp.7947-7955

ABSTRACT The growth kinetics of colloidal Bi(2)S(3) nanorods was investigated. After nucleation, the length distribution of the growing Bi(2)S(3) nanorods narrows with the reaction time until a bimodal length distribution appears. From this critical reaction time on, the smallest nanorods of the ensemble dissolve, feeding with monomer the growth of the largest ones. A comprehensive characterization of the size-distribution evolution of Bi(2)S(3) nanorods is used here to illustrate the dependences of the anisotropic growth rates of cylindrical nanoparticles on the nanoparticle dimensions and the monomer concentration in solution. With this goal in mind, a diffusion-reaction model is presented to explain the origin of the experimentally obtained out length distribution focusing mechanism. The model is able to reproduce the decrease of the growth rate in the nanorod axial direction with both its thickness and length. On the other hand, low lateral reaction rates prevent the nanorod thickness distribution to be focused. In both crystallographic growth directions, a concentration-dependent critical thickness exists, which discriminates between nanorods with positive growth rates and those dissolving in the reaction solution.

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    Article: Core-shell Nanoparticles as Building Blocks for the Bottom-Up Production of Functional Nanocomposites: PbTe-PbS Thermoelectric Properties.
    Maria Ibáñez, Reza Zamani, Stephane Gorsse, Jiandong Fan, Silvia Ortega, Doris Cadavid, Joan Ramon Morante, Jordi Arbiol, Andreu Cabot
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    ACS Nano 02/2013; · 10.77 Impact Factor
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