Size-Dependent Phase Transformation Kinetics in Nanocrystalline ZnS
- 1 March 2005
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 127 (12), 4523-4529
- https://doi.org/10.1021/ja048121c
Abstract
Nanocrystalline ZnS was coarsened under hydrothermal conditions to investigate the effect of particle size on phase transformation kinetics. Although bulk wurtzite is metastable relative to sphalerite below 1020 °C at low pressure, sphalerite transforms to wurtzite at 225 °C in the hydrothermal experiments. This indicates that nanocrystalline wurtzite is stable at low temperature. High-resolution transmission electron microscope data indicate there are no pure wurtzite particles in the coarsened samples and that wurtzite only grows on the surface of coarsened sphalerite particles. Crystal growth of wurtzite stops when the diameter of the sphalerite−wurtzite interface reaches ∼22 nm. We infer that crystal growth of wurtzite is kinetically controlled by the radius of the sphalerite−wurtzite interface. A new phase transformation kinetic model based on collective movement of atoms across the interface is developed to explain the experimental results.Keywords
This publication has 18 references indexed in Scilit:
- Twist Elasticity and Anchoring in a Lamellar Nematic PhasePhysical Review Letters, 2004
- The Role of Oriented Attachment Crystal Growth in Hydrothermal Coarsening of Nanocrystalline ZnSThe Journal of Physical Chemistry B, 2003
- Water-driven structure transformation in nanoparticles at room temperatureNature, 2003
- Understanding Polymorphic Phase Transformation Behavior during Growth of Nanocrystalline Aggregates: Insights from TiO2The Journal of Physical Chemistry B, 2000
- Structure and Stability of Monodisperse 1.4-nm ZnS Particles Stabilized by MercaptoethanolLangmuir, 1999
- Imperfect Oriented Attachment: Dislocation Generation in Defect-Free NanocrystalsScience, 1998
- Pressure-Induced Structural Transformations in Si Nanocrystals: Surface and Shape EffectsPhysical Review Letters, 1996
- Forward and reverse high-pressure transitions in bulklike AlAs and GaAs epilayersPhysical Review B, 1992
- High-pressure phase transition and phase diagram of gallium arsenidePhysical Review B, 1991
- Mechanism of phase transformations in ZnSPramana, 1984