TITLE:
Structural, Optical and Room Temperature Magnetic Study of Mn2O3 Nanoparticles
AUTHORS:
Majed Sharrouf, Ramadan Awad, Mohamad Roumié, Salem Marhaba
KEYWORDS:
Nanoparticles, PIXE, RBS, X-Ray Diffraction, Room Temperature, Antiferromagnetic
JOURNAL NAME:
Materials Sciences and Applications,
Vol.6 No.10,
October
16,
2015
ABSTRACT: In this work, Mn2O3 nanoparticles (NPs) are prepared by co-precipitation technique. The synthesized
sample is characterized by X-ray powder diffraction (XRD). The XRD spectrum reveals the
cubic structure of Mn2O3 NPs and the lattice parameter is calculated to be 9.4232 ?. Crystallite size
(D) is estimated using Debye-Scherer’s formula and is found to be 17.3 nm. A micrograph for the
NPs is obtained using Transmission Electron Microscopy (TEM). The Mn2O3 nanoparticles are
viewed at 7500× magnification and their shape is spherical. D is also measured using TEM and it is
19.1 nm, which is very close to the one obtained from XRD. The elemental contents of the prepared
samples are determined using particle induced X-ray emission (PIXE). In addition, the oxygencontent
of the sample is obtained using non Rutherford backscattering spectroscopy (RBS) at 3
MeV proton beam. The sample shows high purity and the RBS technique is more accurate in determining
the O-content. The presence of functional groups and the chemical bonding is confirmed
by FTIR spectrum. The energy band gap (Eg) is calculated for the NPs using the UV-visible optical
spectroscopy between 350 nm and 800 nm and found to be 1.24 eV. The sample shows high absorption
in the visible range. The magnetization (VSM) is conducted to the sample and the saturation
magnetization (Ms) is calculated as 2.642 emu/g. The hysteresis loop shows antiferromagnetic
behavior. The EPR analysis is performed at room temperature for the NPs. The g-factor is calculated
from the spectrum and found to be 1.985, and the magnetic field shift occurs at Bo = 350.5
mT. The intensity appeared to be high, which confirms the existence of Mn2+ ions on the surface.