Preparation of Nano Ferrite Particle by Chemical Way in High Static Magnetic Field(HSMF)

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Preparation of Nano Ferrite Particle by Chemical
Way in High Static Magnetic Field(HSMF)

• Yunbo Zhong, Li Zhihua, Zhongming Ren
• Shanghai University

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Process of Material in HSMF
Metallic Material
Nano-Material
HSMF
Organic or Biological Material
Inorganic Non-metallic Material
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Methods for Preparation of Nano-particle
1?High Energy Grinding 2?Evaporation 3?Co-Precip
itation 4?Sol-Gel 5?Hydrothermal
Preparation 6?By Plasma And so on
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Several Questions About Preparation of Nano
Material by Chemical Way in HSMF

1. Will Magnetic Field Effect the Process of
   Chemical Reaction?
2. Will Magnetic Field Effect the Process of
   Sediment/nucleation of Nano Particle?
3. Will Magnetic Field Effect the Growth of the Nano
   Particle?
4. Will Magnetic Field Effect the Performance of
   Nano Material?

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Why select Ferrite

• Ferrite is widely used in electric power/electron
  and communication industry
• Nano ferrite material has better performance
• In some usage, shape anisotropy of nano ferrite
  will be welcome for its excellent magnetic
  property
• How magnetic field effect the chemical reaction
  process is not well studied

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Equipment for Experiment
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Distribution of MFD in High Static Magnetic Field
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Flow Chart of Experimental
Control pH
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B0T?Temp80??Adding time of reactant
solution1hr?pH78
B10T?temp80??Adding time of reactant
solution6hrs?pH78
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Effect of temp. on Shape of sediment
40?
50?
60?
70?
B10T?Adding time of reactant solution6hrs?pH78

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In Aqueous Solution, the Critical radius of New
Nucleus is
rp-Critical radius of New Nucleus s-Surface
Energy between Particle and Solution ?-Volume
of Solution K- Boltzman Constant T-Temperature
of Solution C-Actual Concentration of Solute
C-Saturation Concentration of Solute When
Equilibium
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Effect of Adding time of reactant solution on
Shape of sediment
6hrs
2hrs
Adding time of reactant solution
B10T?Temp60??pH78
10hrs
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Effect of MFD on Shape of sediment
B0.3T
B0.5T
B0.6T
B0.7T
Temp60??Adding time of reactant
solution1h?pH78
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Effect of MFD on Shape of sediment
B4T
B10T
Temp80 ?t6hPH79
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Sketch map of the mechanism of effect of Magnetic
Field on nucleation and growth of nano-particle
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Energy spectrum analysis of sediment
a
b
c
d
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Composition of Particles
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X-ray diffraction spectrum
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Main Phase Composition of Particle
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TEM Image of Non-Claviform Particle
Bright Image
Dark Image
Electron Diffraction Image
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TEM Image of Claviform Particle
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Next Step Work
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Conclusions

1. HSMF will effect the nucleation of chemical
   sediment process, and there is a critical MFD,
   Above which the nucleation will grow into
   stick-like or fibre-like
2. The claviform particle by HSMF shows the
   structure of crystal, while the polygonal
   particle is the mixture of non crystal and
   crystal
3. The HSMF will not only effect the shape of
   sediment, but also the phase composition

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Acknowledgement
This work was financial supported by Scientific
Technological Committee of Shanghai Thankful to
sino-German Center for Research Promotion for
financial support to workshop
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Thank you for your attention