Dresden 2014 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 4: Crystallization, Nucleation and Self Assembly I

CPP 4.5: Vortrag

Montag, 31. März 2014, 10:30–10:45, ZEU 114

Growth of nanoparticles - from milliseconds to hours — •Torben Schindler, Martin Schmiele, Tilo Schmutzler, Thaer Kassar, and Tobias Unruh — Lehrstuhl für Kristallographie und Strukturphysik, Friedrich-Alexander-Universität Erlangen Nürnberg, Staudtstr. 3, 91058 Erlangen

Zinc oxide is a promising semiconductor material, which shows interesting optical and electronical properties on the nanoscale and makes it a promising candidate for many applications, e.g. solar cells. However, detailed knowledge about the kinetics of nucleation and growth of the nanoparticles is crucial for a targeted production.

The nanoparticles are synthesized by simply mixing a precursor and an alkaline solution. The growth of the nanoparticles can be studied using in-situ time-resolved small angle X-ray scattering (SAXS). A stopped flow device at a synchrotron SAXS instrument enabled us to determine the size of the nanoparticles as early as 5 ms after the synthesis, with which we could detect a strong increase of the particle diameter especially within the first 200 ms. In addition, an unexpected behavior was observed using triethylamine as alkaline solution. The particle diameters are fluctuating on a ms-timescale during the ripening process. These findings will be presented with additional absorption spectroscopy studies to describe the time- and temperature-dependent ripening process of differently synthesized ZnO nanoparticles from milliseconds to hours.