Physical Properties of Mn{sub 2}O{sub 3} Nanoparticles Synthesized by Co-precipitation Method at Different pH Values

Journal Article · Mon Apr 15 00:00:00 EDT 2019 · Journal of Superconductivity and Novel Magnetism

DOI:https://doi.org/10.1007/S10948-018-4765-X· OSTI ID:22921340

Awad, R. ^[1]; Abdel-Gaber, A. M. ^[2]

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1. Beirut Arab University, Department of Physics, Faculty of Science (Lebanon)
2. Beirut Arab University, Department of Chemistry, Faculty of Science (Lebanon)

Mn{sub 2}O{sub 3} nanoparticles were synthesized at different pH values ranging from 10 to 13 by co-precipitation technique. The characterization of all samples were completed by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), ultraviolet-absorption spectroscopy (UV), Raman spectroscopy, and M–H loop measurements. The XRD spectra show that the structure of Mn{sub 2}O{sub 3} is cubic, and the lattice parameter a decreases as pH increases. Crystalline size, determined from TEM and XRD analyses, decreases as pH increases. TGA curves show that a mass loss is significantly affected as pH increases, indicating the decomposition of organic species besides the oxidation of Mn{sub 2}O{sub 3} to Mn{sub 3}O{sub 4}. FTIR spectra indicate that the absorption peaks at 593.73 and 519.09 cm{sup − 11} referred to the stretching vibration of Mn–O and Mn–O–Mn bonds during the synthesis of Mn{sub 2}O{sub 3} nanoparticles. UV-visible spectroscopy is measured in the range 250–800 nm and showed a deviation to the lower wavelength in addition to an increase in the band-gap energy (E{sub g}) values from 1.012 to 1.370 eV is obtained. Raman spectra shows a slight deviation to the left which is conversely proportional to the crystalline size. M–H loops for the prepared samples were measured and the results of retentivity (M{sub s}) and coercivity (H{sub c}) were discussed.

• OSTI ID: 22921340
• Journal Information: Journal of Superconductivity and Novel Magnetism, Journal Name: Journal of Superconductivity and Novel Magnetism Journal Issue: 4 Vol. 32; ISSN 1557-1939
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ABSORPTION
ABSORPTION SPECTROSCOPY
COERCIVE FORCE
COPRECIPITATION
ENERGY GAP
FOURIER TRANSFORMATION
INFRARED SPECTRA
LATTICE PARAMETERS
MANGANESE OXIDES
MASS TRANSFER
NANOPARTICLES
OXIDATION
PH VALUE
PHYSICAL PROPERTIES
RAMAN SPECTRA
RAMAN SPECTROSCOPY
SYNTHESIS
THERMAL GRAVIMETRIC ANALYSIS
TRANSMISSION ELECTRON MICROSCOPY
ULTRAVIOLET RADIATION
X-RAY DIFFRACTION