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Title: Kinetically Controlled Formation of a Novel Nanoparticulate ZnS with Mixed Cubic and Hexagonal Stacking

Abstract

Nanoparticulate ZnS with mixed cubic and hexagonal close packed stacking was synthesized by reaction of zinc acetate with thioacetamide in weakly acidic solutions. The influences of temperature, reaction time, amounts of reagents and solution pH on the nanoparticle size and phase constitution were investigated. Experimental results suggest that the stacking in the nano-ZnS is controlled primarily by the precipitation kinetics. Factors that slow the precipitation rate favor the growth of nanoparticles with mixed stacking, probably because the probabilities of forming wurtzite-like layers and sphalerite-like layers under these conditions are approximately equal. Under conditions of rapid precipitation, the growth of sphalerite is favored, probably due to the aggregation of molecular clusters with sphalerite-like structure. UV-vis spectroscopy reveals that twins and stacking faults in nano-ZnS result in an electronic structure that differs from those of nano-scale sphalerite and wurtzite. New vibrational modes present in IR spectra of the nano-ZnS with mixed stacking indicate that the materials have novel optical properties. Control of defect microstructure may allow use of nano-ZnS in new technological applications.

Authors:
; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
913950
Report Number(s):
BNL-78518-2007-JA
Journal ID: ISSN 0959-9428; JMACEP; TRN: US200804%%301
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: J Mater. Chem.; Journal Volume: 16; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ZINC SULFIDES; SYNTHESIS; NANOSTRUCTURES; CUBIC LATTICES; HEXAGONAL LATTICES; REACTION KINETICS; PRECIPITATION; ELECTRONIC STRUCTURE; STACKING FAULTS; TWINNING; OPTICAL PROPERTIES; national synchrotron light source

Citation Formats

Zhang,H., Chen, B., Gilbert, B., and Banfield, J. Kinetically Controlled Formation of a Novel Nanoparticulate ZnS with Mixed Cubic and Hexagonal Stacking. United States: N. p., 2006. Web. doi:10.1039/b512580d.
Zhang,H., Chen, B., Gilbert, B., & Banfield, J. Kinetically Controlled Formation of a Novel Nanoparticulate ZnS with Mixed Cubic and Hexagonal Stacking. United States. doi:10.1039/b512580d.
Zhang,H., Chen, B., Gilbert, B., and Banfield, J. Sun . "Kinetically Controlled Formation of a Novel Nanoparticulate ZnS with Mixed Cubic and Hexagonal Stacking". United States. doi:10.1039/b512580d.
@article{osti_913950,
title = {Kinetically Controlled Formation of a Novel Nanoparticulate ZnS with Mixed Cubic and Hexagonal Stacking},
author = {Zhang,H. and Chen, B. and Gilbert, B. and Banfield, J.},
abstractNote = {Nanoparticulate ZnS with mixed cubic and hexagonal close packed stacking was synthesized by reaction of zinc acetate with thioacetamide in weakly acidic solutions. The influences of temperature, reaction time, amounts of reagents and solution pH on the nanoparticle size and phase constitution were investigated. Experimental results suggest that the stacking in the nano-ZnS is controlled primarily by the precipitation kinetics. Factors that slow the precipitation rate favor the growth of nanoparticles with mixed stacking, probably because the probabilities of forming wurtzite-like layers and sphalerite-like layers under these conditions are approximately equal. Under conditions of rapid precipitation, the growth of sphalerite is favored, probably due to the aggregation of molecular clusters with sphalerite-like structure. UV-vis spectroscopy reveals that twins and stacking faults in nano-ZnS result in an electronic structure that differs from those of nano-scale sphalerite and wurtzite. New vibrational modes present in IR spectra of the nano-ZnS with mixed stacking indicate that the materials have novel optical properties. Control of defect microstructure may allow use of nano-ZnS in new technological applications.},
doi = {10.1039/b512580d},
journal = {J Mater. Chem.},
number = 3,
volume = 16,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • No abstract prepared.
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