| Summary: | Manganese Ferrite Nanoparticles (MnFe2O4) has been fabricated by
coprecipitation method with various synthesis temperature, concentration of
NaOH and duration of stirring. The structural characteristics and particle sizes of
MnFe2O4 were determined by X-ray diffraction (XRD) and Transmission Electron
Microscopy (TEM), it is showed that nanoparticles well crystallized with various
grain size which depend on synthesis parameters. The grain sizes was calculated
by Scherrer formula showed that the grain size increased with increasing
temperature synthesis and decreasing concentration of NaOH and stirring
duration. With the smallest grain size of the sample A was 14 ± 0.1 nm at 80 ° C,
10 M concentration of NaOH and stirring duration 120 minute. Magnetic
characterization of MnFe2O4 nanoparticles was investigated by using a Vibrating
Sample Magnetometer (VSM) at sample with various concentration of NaOH
showed that coercivity was decrease with the decrease of particle size. In other
hand, samples with various synthesis temperature and strirring duration found that
sample with smallest grain size have high coersivity. Saturation magnetization is
affected by the presence of an impurity phase hematite (α-Fe2O3). Based on
magnetic characterization analysis sample have been chosen sample A (
temperature 80°C, concentration of NaOH 10 M and stirring duration 120
minutes) to modified with PEG-4000. XRD analysis showed that modification
with PEG-4000 given increasing degree of crystallinity. VSM analysis showed
that modification with PEG-4000 given decreasing saturation was predicted
because of phase lepidocrocite γ-FeO(OH) results from bonding occurs between
MnFe2O4 with PEG-4000 which shown at XRD.
Key words: nanoparticles, MnFe2O4, co-presipitation, PEG-4000
|
|---|