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Title: Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions

Abstract

Cobalt monoxide (CoO) nanocrystals were synthesized by thermal decomposition of cobalt oleate precursor in a high boiling point organic solvent 1-octadecene. The X-ray diffraction pattern and transmission electron microscopy studies suggest that pure face-centered-cubic (fcc) phase of CoO can be synthesized in the temperature range of 569–575 K. Thermolysis product at higher synthesis temperature 585 K is a mixture of fcc and hexagonal-closed-packed (hcp) phases. These nanocrystals are single crystals of CoO and exhibit mixture of two types of morphologies; one is nearly spherical with 5–25 nm diameter, and other one is 5–10 nm thick flake. The pure fcc-CoO nanocrystals show enhanced, and mixture of fcc- and hcp-CoO nanocrystals show reduced antiferromagnetic ordering temperature. Such results provide new opportunities for optimizing and enhancing the properties and performance of cobalt oxide nanomaterials.

Authors:
; ;  [1]; ;  [2]
  1. Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India)
  2. Laboratoire CRISMAT, CNRS UMR 6508, ENSICAEN, 6 Bd du Marechal Juin, F-14050 Caen Cedex (France)
Publication Date:
OSTI Identifier:
22308483
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ANTIFERROMAGNETISM; COBALT OXIDES; FCC LATTICES; HCP LATTICES; MONOCRYSTALS; NANOMATERIALS; NANOSTRUCTURES; OPTIMIZATION; PYROLYSIS; SPHERICAL CONFIGURATION; SYNTHESIS; TEMPERATURE RANGE 0400-1000 K; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Ravindra, A. V., Behera, B. C., Padhan, P., Lebedev, O. I., and Prellier, W. Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions. United States: N. p., 2014. Web. doi:10.1063/1.4890512.
Ravindra, A. V., Behera, B. C., Padhan, P., Lebedev, O. I., & Prellier, W. Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions. United States. doi:10.1063/1.4890512.
Ravindra, A. V., Behera, B. C., Padhan, P., Lebedev, O. I., and Prellier, W. Mon . "Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions". United States. doi:10.1063/1.4890512.
@article{osti_22308483,
title = {Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions},
author = {Ravindra, A. V. and Behera, B. C. and Padhan, P. and Lebedev, O. I. and Prellier, W.},
abstractNote = {Cobalt monoxide (CoO) nanocrystals were synthesized by thermal decomposition of cobalt oleate precursor in a high boiling point organic solvent 1-octadecene. The X-ray diffraction pattern and transmission electron microscopy studies suggest that pure face-centered-cubic (fcc) phase of CoO can be synthesized in the temperature range of 569–575 K. Thermolysis product at higher synthesis temperature 585 K is a mixture of fcc and hexagonal-closed-packed (hcp) phases. These nanocrystals are single crystals of CoO and exhibit mixture of two types of morphologies; one is nearly spherical with 5–25 nm diameter, and other one is 5–10 nm thick flake. The pure fcc-CoO nanocrystals show enhanced, and mixture of fcc- and hcp-CoO nanocrystals show reduced antiferromagnetic ordering temperature. Such results provide new opportunities for optimizing and enhancing the properties and performance of cobalt oxide nanomaterials.},
doi = {10.1063/1.4890512},
journal = {Journal of Applied Physics},
number = 3,
volume = 116,
place = {United States},
year = {Mon Jul 21 00:00:00 EDT 2014},
month = {Mon Jul 21 00:00:00 EDT 2014}
}
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