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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. Process of Material in HSMF. Metallic Material. Nano-Material. HSMF. Inorganic Non-metallic Material. Organic or Biological Material.
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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
Process of Material in HSMF Metallic Material Nano-Material HSMF Inorganic Non-metallic Material Organic or Biological Material
Methods for Preparation of Nano-particle 1、High Energy Grinding; 2、Evaporation; 3、Co-Precipitation; 4、Sol-Gel; 5、Hydrothermal Preparation; 6、By Plasma; And so on…………
Several Questions About Preparation of Nano Material by Chemical Way in HSMF • Will Magnetic Field Effect the Process of Chemical Reaction? • Will Magnetic Field Effect the Process of Sediment/nucleation of Nano Particle? • Will Magnetic Field Effect the Growth of the Nano Particle? • Will Magnetic Field Effect the Performance of Nano Material?
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;
Mixture of Iron Nitrate, Manganese Nitrate and Zinc Nitrate Solution Ammonia Thermocouple Nitrogen PID Temperature Controller Quartz Pipe pH Meter pH Probe Buffer Solution Heater Superconductive Coil Heat Resistant Fibre Water-cooling Pipe Superconductive Magnet Equipment for Experiment
Distribution of MFD in High Static Magnetic Field
(Fe、Mn、Zn)NO3 Mixture Ammonia Liquid NH4HCO3Solution Co-Precipitation Filtration Abstersion Drying SEM、TEM Flow Chart of Experimental Control pH
B=0T、Temp=80℃、Adding time of reactant solution=1hr、pH=7~8 B=10T、temp=80℃、Adding time of reactant solution=6hrs、pH=7~8
Effect of temp. on Shape of sediment 50℃ 40℃ 70℃ 60℃ B=10T、Adding time of reactant solution=6hrs、pH=7~8
In Aqueous Solution, the Critical radius of New Nucleus is rp-Critical radius of New Nucleus; σ-Surface Energy between Particle and Solution; υ-Volume of Solution; K- Boltzman Constant; T-Temperature of Solution; C-Actual Concentration of Solute; C*-Saturation Concentration of Solute When Equilibium;
Effect of Adding time of reactant solution on Shape of sediment 6hrs 2hrs Adding time of reactant solution B=10T、Temp=60℃、pH=7~8 10hrs
Effect of MFD on Shape of sediment B=0.3T B=0.5T B=0.6T B=0.7T Temp=60℃、Adding time of reactant solution=1h、pH=7~8
Effect of MFD on Shape of sediment B=4T B=10T Temp=80 ℃;t=6h;PH=7~9
Claviform Particle Solution Aggregate Particle High static magnetic field Without magnetic field Critical magnetic field Sketch map of the mechanism of effect of Magnetic Field on nucleation and growth of nano-particle
Iron Atomic % Maganese Atomic % Zinc Atomic % Fe:Mn Fe:Zn 14.19 17.72 1.30 0.8 10.91 21.14 18.30 2.32 1.155 9.112 c-Block Particle 22.75 5.85 0.03 3.889 758.33 a-Claviform Particle d-Block Particle 22.91 5.08 0.66 4.51 34.71 b-Claviform Particle Composition of Particles
Iron Manganese Zinc 0T Iron Tetroxide Manganese Tetroxide None 10T Iron Trioxide Manganese Trioxide Zinc Ferrite Main Phase Composition of Particle
TEM Image of Non-ClaviformParticle Bright Image Dark Image Electron Diffraction Image
Fibre Nano Particle Alignment in HSMF Sintering Performance Measurement Next Step Work
Conclusions • 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; • The claviform particle by HSMF shows the structure of crystal, while the polygonal particle is the mixture of non crystal and crystal; • The HSMF will not only effect the shape of sediment, but also the phase composition;
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