AI Article Synopsis
- The study investigates how copper nanoparticles form in barium-phosphate glass using in situ optical micro-spectroscopy, providing insight into their nucleation and growth kinetics.
- It identifies two stages of nanoparticle precipitation: pre-plasmonic and plasmonic, with activation energies of 3.9 eV and 2.6 eV for each stage, respectively.
- The research applies classical nucleation theory and suggests a link between diffusion activation energy and glass transition temperature for broader understanding.
Article Abstract
The kinetics of copper nanoparticle (NP) precipitation in melt-quenched barium-phosphate glass has been studied by in situ isothermal optical micro-spectroscopy. A spectroscopically based approximation technique is proposed to obtain information about the activation energies of nucleation and growth in a narrow temperature range (530-570 °C). Pre-plasmonic and plasmonic NP precipitation stages are identified separated in time. The process as a whole is discussed employing classical nucleation/growth theory and the Kolmogorov-Johnson-Mehl-Avrami phase change model. Activation energies of 3.9(7) eV and 2.6(5) eV have been estimated for the pre-plasmonic and plasmonic spectroscopically assessed stages, respectively. High resolution transmission electron microscopy, differential scanning calorimetry, and Raman spectroscopy were used as complementary techniques for studying the nanoparticulate phase and glass host structure. An empirical linear dependence of the diffusion activation energy on the glass transition temperature with broad applicability is suggested.
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| http://dx.doi.org/10.1039/c4cp04662e | DOI Listing |
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