Dissertation > Excellent graduate degree dissertation topics show

Synthesis, Characterization and Applications of Magnetic Composite Nano-materials

Author: ZhangXuePing
Tutor: JiangWanQuan
School: University of Science and Technology of China
Course: Analytical Chemistry
Keywords: magnetic nano-materials sonochemical superparamagnetic catalysis
CLC: TB383.1
Type: Master's thesis
Year: 2010
Downloads: 183
Quote: 2
Read: Download Dissertation

Abstract


As a broad used basic functional materials,the application of magnetic nano-materials have penetrated into every aspects of national economy and national defense science and technology. The particle size and structure determine the final properties of the magnetic nano-materials. Therefore, it is believed that the synthesis of magnetic nano-materials with novel structure and unique properties play a significant role in expanding its application. In this work, magnetic nano composties based on Fe3O4 have been synthesized. The details are as the follows:1. Firstly, we briefly introduced the importance and general trend of magnetic nano-materials. Secondly, the basic properties of magnetic nano-materials were introduced. Thirdly, we provided an overview of the application and the synthesis of magnetic nano-materials. Finally, a brief introduction of magnetic nanocomposites was summarized.2. A Fe3O4/Ag composite, with high efficiency in the degradation of Rhodamine B was synthesized through a simple sonochemical method. A formation mechanism was proposed and discussed. This sonochemical method is attractive since it eliminated the use of any reductants, which is necessary to transform the Ag+ to the Ag0. In comparison to high temperature or high pressure experimental processes, this method is mild, inexpensive, green and efficient. The M-H hysteresis loop of these Fe3O4/Ag composite microspheres indicates that the composite microspheres exhibit superparamagnetic characteristics at room temperature. Furthermore, these composites can be recycled six times by magnetic separation without major loss of activity.3. Fe3O4-TiO2 photocatalyst was synthesized by a novel sonochemical method. This method is attractive since it eliminated a high-temperature heat treatment required in conventional sol-gel method, which is important in transforming amorphous titanium dioxide into a photoactive crystalline phase. In comparison to other methods, the developed method is simple, mild, green and efficient. The M-H hysteresis loop for Fe3O4-TiO2 indicates that the hybrid catalysts show superparamagnetic characteristics at room temperature. Photocatalytic activity studies confirm the as-prepared nano composites have high photocatalytic ability toward the photodegradation of Rhodamine B solution. Furthermore, the photodecomposition rate decreases only slightly after six cycles of the photocatalysis experiment.4. This chapter reports the fabrication of a novel rattle-type nanocatalysts system possessing a well-defined core of hierarchical nickel silicate （NS） protected superparamagnetic Fe3O4 nanocrystals and a layer of uniform Ag nanoparticles on the outer shell by a multi-step approach and their applications as magnetically recoverable catalysts for the degradation of tetranitro-phenol. As a result, the multifunctional well-designed microspheres showed high performance in the reduction of tetranitro-phenol and the rate of the catalytic reaction can be controlled by changing the concentration of nanocatalysts. In particular, there was no visible decrease in the catalytic activity of the reused catalysts even after being recycled 8 times （average 99.9 %）, from which it can be deduced that Fe3O4@NS partices are very suitable as catalysts support for catalysts separation and redispersion.

Related Dissertations

  1. Synthesis and Reactions of Organo Lithium, Potassium, Magnesium Compounds,O621.13
  2. Synthesis and Asymmetric Catalytic Behaviors of Chiral Imine and Dimines Schiff Bases,O621.3
  3. Sulfonamide substitution reaction catalyzed asymmetric,O621.25
  4. Syntheses, Structures and Properties of Transition Metal Complexes Based on Pyridyl Ligands,O627.2
  5. Cp-PMO and Co-PMO: Preparation, Characterization and Catalytic Performance,O643.3
  6. Preparation and Characterization of Multifunctional Fe3O4/ZnO/SiIO2 Nanocomposites,TB383.1
  7. The Design of Chial β-Amino Alcohols and their Application to the Asymmetric Henry Reaction and the Asymmetric Reduction of Prochiral Ketones,O643.32
  8. Accelerometer suspension maglev research,TH824.4
  9. Containing silver nanoparticles temperature stimuli-responsive hybrid nano- hydrogels,TB383.1
  10. Degradation of dielectric barrier discharge combined with studies of gaseous benzene,O621.2
  11. Stereoselective Reduction of Prochiral Carbonyl Compounds by Photo-biocatalysis with Microalgae,O643.32
  12. Experimental study of the copper residue catalytic pyrolysis gas , chemical and biological substances,X758
  13. Gallic Acid Production Wastewater and Waste Residue Treatment and Utilization,X703
  14. Research on Lipase-catalyzed Preparation of Rice Bran Oil Rich in DAG with High Acid Rice Bran Oil,TS225
  15. Preparation of Gold-Maghemite Nanocomposites,TB383.1
  16. Study on the Synthesis of Tmpde and the Measurement of Vapor-Liquid Equilibrium of the Mixture,TQ225.2
  17. Synthesis, Characterization, Catalytic Activity and Magnetic Property of Novel Organolanthanide Macrocycles with a Bridged Dipyrrolide Ligand,O627.3
  18. Synthesis, Characterization and Catalvtic Activitv of Organolanide Complexes with Me8-calix[4] Pvrrole Ligands,O627.3
  19. Study on Syntheses, Characterization and Application as a Catalyst of Chiral Diam Inocyclohexane Schiffbases Complexes,O621.25
  20. L-proline’s Derivatives Catalyzed Asymmetric Michael Addition,TQ203.2

CLC: > Industrial Technology > General industrial technology > Materials science and engineering > Special structural materials
© 2012 www.DissertationTopic.Net  Mobile