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Title: High resolution electron energy loss spectroscopy of manganese oxides: Application to Mn{sub 3}O{sub 4} nanoparticles

Abstract

Manganese oxides particularly Mn{sub 3}O{sub 4} Hausmannite are currently used in many industrial applications such as catalysis, magnetism, electrochemistry or air contamination. The downsizing of the particle size of such material permits an improvement of its intrinsic properties and a consequent increase in its performances compared to a classical micron-sized material. Here, we report a novel synthesis of hydrophilic nano-sized Mn{sub 3}O{sub 4}, a bivalent oxide, for which a precise characterization is necessary and for which the determination of the valency proves to be essential. X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and particularly High Resolution Electron Energy Loss Spectroscopy (HREELS) allow us to perform these measurements on the nanometer scale. Well crystallized 10-20 nm sized Mn{sub 3}O{sub 4} particles with sphere-shaped morphology were thus successfully synthesized. Meticulous EELS investigations allowed the determination of a Mn{sup 3+}/Mn{sup 2+} ratio of 1.5, i.e. slightly lower than the theoretical value of 2 for the bulk Hausmannite manganese oxide. This result emphasizes the presence of vacancies on the tetrahedral sites in the structure of the as-synthesized nanomaterial. - Research Highlights: {yields}Mn{sub 3}O{sub 4} bulk and nano were studied by XRD, TEM and EELS. {yields}XRD and TEM determine the degree of crystallinity and themore » narrow grain size. {yields}HREELS gave access to the Mn{sup 3+}/Mn{sup 2+} ratio. {yields}Mn{sub 3}O{sub 4} nano have vacancies on the tetrahedral sites.« less

Authors:
 [1];  [2]
  1. Institut Carnot, Laboratoire CIRIMAT (equipe MEMO), CNRS UMR 5085, ENSIACET, 4 allee Emile Monso, BP 74233, 31432 Toulouse cedex 4 (France)
  2. Laboratoire de Reactivite et Chimie des Solides CNRS UMR 6007, Universite de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens cedex 9 (France)
Publication Date:
OSTI Identifier:
22066246
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 61; Journal Issue: 11; Other Information: Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; CATALYSIS; ELECTROCHEMISTRY; ENERGY-LOSS SPECTROSCOPY; GRAIN SIZE; MAGNETISM; MANGANESE IONS; MANGANESE OXIDES; MORPHOLOGY; NANOSTRUCTURES; PARTICLE SIZE; PARTICLES; SYNTHESIS; TRANSMISSION ELECTRON MICROSCOPY; VACANCIES; VALENCE; X-RAY DIFFRACTION

Citation Formats

Laffont, L., E-mail: Lydia.laffont@ensiacet.fr, and Gibot, P. High resolution electron energy loss spectroscopy of manganese oxides: Application to Mn{sub 3}O{sub 4} nanoparticles. United States: N. p., 2010. Web. doi:10.1016/J.MATCHAR.2010.09.001.
Laffont, L., E-mail: Lydia.laffont@ensiacet.fr, & Gibot, P. High resolution electron energy loss spectroscopy of manganese oxides: Application to Mn{sub 3}O{sub 4} nanoparticles. United States. doi:10.1016/J.MATCHAR.2010.09.001.
Laffont, L., E-mail: Lydia.laffont@ensiacet.fr, and Gibot, P. 2010. "High resolution electron energy loss spectroscopy of manganese oxides: Application to Mn{sub 3}O{sub 4} nanoparticles". United States. doi:10.1016/J.MATCHAR.2010.09.001.
@article{osti_22066246,
title = {High resolution electron energy loss spectroscopy of manganese oxides: Application to Mn{sub 3}O{sub 4} nanoparticles},
author = {Laffont, L., E-mail: Lydia.laffont@ensiacet.fr and Gibot, P.},
abstractNote = {Manganese oxides particularly Mn{sub 3}O{sub 4} Hausmannite are currently used in many industrial applications such as catalysis, magnetism, electrochemistry or air contamination. The downsizing of the particle size of such material permits an improvement of its intrinsic properties and a consequent increase in its performances compared to a classical micron-sized material. Here, we report a novel synthesis of hydrophilic nano-sized Mn{sub 3}O{sub 4}, a bivalent oxide, for which a precise characterization is necessary and for which the determination of the valency proves to be essential. X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and particularly High Resolution Electron Energy Loss Spectroscopy (HREELS) allow us to perform these measurements on the nanometer scale. Well crystallized 10-20 nm sized Mn{sub 3}O{sub 4} particles with sphere-shaped morphology were thus successfully synthesized. Meticulous EELS investigations allowed the determination of a Mn{sup 3+}/Mn{sup 2+} ratio of 1.5, i.e. slightly lower than the theoretical value of 2 for the bulk Hausmannite manganese oxide. This result emphasizes the presence of vacancies on the tetrahedral sites in the structure of the as-synthesized nanomaterial. - Research Highlights: {yields}Mn{sub 3}O{sub 4} bulk and nano were studied by XRD, TEM and EELS. {yields}XRD and TEM determine the degree of crystallinity and the narrow grain size. {yields}HREELS gave access to the Mn{sup 3+}/Mn{sup 2+} ratio. {yields}Mn{sub 3}O{sub 4} nano have vacancies on the tetrahedral sites.},
doi = {10.1016/J.MATCHAR.2010.09.001},
journal = {Materials Characterization},
number = 11,
volume = 61,
place = {United States},
year = 2010,
month =
}
  • The scattering of low energy electrons by metal surfaces has been studied for many years now. The electron's ease of generation and detection and high surface sensitivity (low penetration depth) make it an ideal probe for surface scientists. The impinging electron can interact with the surface in basically two ways: it can either elastically reflect (or diffract) from the surface without losing energy or lose a portion of it's incident energy and inelastically scatter. In this paper we will be concerned with only one of many possible inelastic scattering processes: the loss of the electron's energy to the vibrational modesmore » of atoms and molecules chemisorbed on the surface. This technique is known as high resolution electron energy loss spectroscopy (or ELS, EELS, HRELS, HREELS, etc.).« less
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  • The scattering of low energy electrons by metal surfaces makes an ideal probe for surface scientists. This paper is concerned with only one of many possible inelastic scattering processes: the loss of the electron's energy to the vibrational modes of atoms and molecules chemisorbed on the surface. This technique is known as high resolution electron energy loss spectroscopy (or ELS, EELS, HRELS, HREELS, etc.). 106 references, 8 figures, 3 tables.
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