Third Day Poster Session, 17 June 2010 - NanoTR-VI

Poster Session, Thursday, June 17
Theme F686 - N1123
PEG assisted synthesis of Mn 3 O 4 Nanoparticles: Structural and Magnetic Study
A.Baykal 1 *, M.Toma 1 , Z.Durmus 1 , H.Kavas 2 and M.S.Toprak 3
1 Department of Chemistry and 2 Physics, Fatih University, B. Cekmece, 34500 Istanbul, Turkey
3 Functional Materials Division, Royal Institute of Technology - KTH, SE16440 Stockholm, Sweden
Abstract- In this work, Mn 3 O 4 nanoparticles have been successfully synthesized by polyethylene glycol (PEG)-assisted
hydrothermal route for the first time. X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), transmission
electron microscopy (TEM) and vibrating scanning magnetometry (VSM), electron spin resonance (ESR) were used for the
structural, morphological and magnetic investigation of the products, respectively.
Among magnetic materials, manganese oxide
(Mn 3 O 4 ) as a magnetic transition metal oxide is an
important material. Nanometer-sized manganese oxide
(Mn 3 O 4 ), with notable increased surface area and greatly
reduced size, is expected to display better performance in
these aspects of application [1]. In this study the crystallite
size from X-ray diffraction pattern and particle size from
transmisson electron micrographs were calculated as 23±1
nm and 24.5±1.5 nm respectively. Transmisson electron
microscopy (TEM) analysis also showed the
polycrystalline nature of the product. Magnetic
characteristics of Mn 3 O 4 NP were evaluated by electron
spin resonance (ESR) measurements in the temperature
range of 24 °K – 294 °K and the Curie temperature was
observed as 43 K. Also the magnetic phases occured in
nano sized Mn 3 O 4 are detected below Tc by this method.
The room temperature paramagnetic characteristic are
verified by vibrating scanning magnetometry (VSM).
1st Derivatives of EPR Absorbtion Peaks
0 1000 2000 3000 4000 5000 6000 7000
Applied Magnetic Field (Oe)
294 K
266 K
230 K
202 K
175 K
153 K
122 K
104 K
74 K
50 K
Figure 2. First derivatives of EPR absorption peaks vs applied
magnetic field at various temperatures above 50 °K.
Intensity (a.u)
..............................................112
exp
fit
D= 23 nm
= 1 nm
.......................................................................200
................103
211
....................................................004
...........................................................220
20 30 40 50 60
2(Degree)
.....................................................................204
......................................................015
..................................................................312
........................................................................303
.......................................................321
................................................................224
........................................................................116
...........................................................400
Figure 1. XRD pattern and line profile fitting of Mn 3 O 4 NP’s via
PEG assisted hydrothermal route.
ESR analysis showed antiferromagnetic interacting
spins at >50 °K and ferromagnetic interacting alignment <
50 °K revealing a Tc of 43 °K in Figure 2 and 3.
1st Derivatives of EPR Absorbtion Peaks
50 K
49 K
47 K
45 K
44 K
42 K
39 K
37 K
36 K
34 K
32 K
31 K
28 K
27 K
24 K
0 1000 2000 3000 4000 5000 6000 7000
Applied Magnetic Field (Oe)
Figure 3. First derivatives of EPR absorption peaks vs applied
magnetic field at various temperatures below 50 °K.
* Corresponding author: hbaykal@fatih.edu.tr
[1] H. Kavas, Z. Durmus, M. enel, S. Kazan, A. Baykal, M.S.
Toprak, Polyhedron doi:10.1016/j.poly.2009.12.034.
6th Nanoscience and Nanotechnology Conference, zmir, 2010 716